Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / whidbey / netfxsp / ndp / fx / src / WinForms / Managed / System / WinForms / LinkLabel.cs / 4 / LinkLabel.cs
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Windows.Forms {
using Microsoft.Win32;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Drawing.Design;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Runtime.Remoting;
using System.Runtime.Serialization.Formatters;
using System.Security;
using System.Security.Permissions;
using System.Text;
using System.Windows.Forms.ComponentModel;
using System.Globalization;
using System.Windows.Forms;
using System.Windows.Forms.Layout;
using System.Windows.Forms.Internal;
using System;
///
///
/// Displays text that can contain a hyperlink.
///
///
[
ComVisible(true),
ClassInterface(ClassInterfaceType.AutoDispatch),
DefaultEvent("LinkClicked"),
ToolboxItem("System.Windows.Forms.Design.AutoSizeToolboxItem," + AssemblyRef.SystemDesign),
SRDescription(SR.DescriptionLinkLabel)
]
public class LinkLabel : Label, IButtonControl {
static readonly object EventLinkClicked = new object();
static Color iedisabledLinkColor = Color.Empty;
static LinkComparer linkComparer = new LinkComparer();
///
/// The dialog result that will be sent to the parent dialog form when
/// we are clicked.
///
DialogResult dialogResult;
Color linkColor = Color.Empty;
Color activeLinkColor = Color.Empty;
Color visitedLinkColor = Color.Empty;
Color disabledLinkColor = Color.Empty;
Font linkFont;
Font hoverLinkFont;
bool textLayoutValid = false;
bool receivedDoubleClick = false;
ArrayList links = new ArrayList(2);
Link focusLink = null;
LinkCollection linkCollection = null;
Region textRegion = null;
Cursor overrideCursor = null;
bool processingOnGotFocus; // used to avoid raising the OnGotFocus event twice after selecting a focus link.
LinkBehavior linkBehavior = System.Windows.Forms.LinkBehavior.SystemDefault;
///
///
/// Initializes a new default instance of the
///
public LinkLabel() : base() {
SetStyle(ControlStyles.AllPaintingInWmPaint
| ControlStyles.OptimizedDoubleBuffer
| ControlStyles.Opaque
| ControlStyles.UserPaint
| ControlStyles.StandardClick
| ControlStyles.ResizeRedraw, true);
ResetLinkArea();
}
///
///
/// Gets or sets the color used to display active links.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelActiveLinkColorDescr)
]
public Color ActiveLinkColor {
get {
if (activeLinkColor.IsEmpty) {
return IEActiveLinkColor;
}
else {
return activeLinkColor;
}
}
set {
if (activeLinkColor != value) {
activeLinkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Gets or sets the color used to display disabled links.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelDisabledLinkColorDescr)
]
public Color DisabledLinkColor {
get {
if (disabledLinkColor.IsEmpty) {
return IEDisabledLinkColor;
}
else {
return disabledLinkColor;
}
}
set {
if (disabledLinkColor != value) {
disabledLinkColor = value;
InvalidateLink(null);
}
}
}
private Link FocusLink {
get {
return focusLink;
}
set {
if (focusLink != value) {
if (focusLink != null) {
InvalidateLink(focusLink);
}
focusLink = value;
if (focusLink != null) {
InvalidateLink(focusLink);
UpdateAccessibilityLink(focusLink);
}
}
}
}
private Color IELinkColor {
get {
return LinkUtilities.IELinkColor;
}
}
private Color IEActiveLinkColor {
get {
return LinkUtilities.IEActiveLinkColor;
}
}
private Color IEVisitedLinkColor {
get {
return LinkUtilities.IEVisitedLinkColor;
}
}
private Color IEDisabledLinkColor {
get {
if (iedisabledLinkColor.IsEmpty) {
iedisabledLinkColor = ControlPaint.Dark(DisabledColor);
}
return iedisabledLinkColor;
}
}
private Rectangle ClientRectWithPadding {
get {
return LayoutUtils.DeflateRect(ClientRectangle, Padding);
}
}
///
///
/// Gets or sets the range in the text that is treated as a link.
///
///
[
Editor("System.Windows.Forms.Design.LinkAreaEditor, " + AssemblyRef.SystemDesign, typeof(UITypeEditor)),
RefreshProperties(RefreshProperties.Repaint),
Localizable(true),
SRCategory(SR.CatBehavior),
SRDescription(SR.LinkLabelLinkAreaDescr)
]
public LinkArea LinkArea {
get {
if (links.Count == 0) {
return new LinkArea(0, 0);
}
return new LinkArea(((Link)links[0]).Start, ((Link)links[0]).Length);
}
set {
LinkArea pt = LinkArea;
links.Clear();
if (!value.IsEmpty) {
if (value.Start < 0) {
throw new ArgumentOutOfRangeException("LinkArea", value, SR.GetString(SR.LinkLabelAreaStart));
}
if (value.Length < -1) {
throw new ArgumentOutOfRangeException("LinkArea", value, SR.GetString(SR.LinkLabelAreaLength));
}
if (value.Start != 0 || value.Length != 0) {
Links.Add(new Link(this));
// Update the link area of the first link
//
((Link)links[0]).Start = value.Start;
((Link)links[0]).Length = value.Length;
}
}
UpdateSelectability();
if (!pt.Equals(LinkArea)) {
InvalidateTextLayout();
LayoutTransaction.DoLayout(ParentInternal, this, PropertyNames.LinkArea);
base.AdjustSize();
Invalidate();
}
}
}
///
///
/// Gets ir sets a value that represents how the link will be underlined.
///
///
[
DefaultValue(LinkBehavior.SystemDefault),
SRCategory(SR.CatBehavior),
SRDescription(SR.LinkLabelLinkBehaviorDescr)
]
public LinkBehavior LinkBehavior {
get {
return linkBehavior;
}
set {
//valid values are 0x0 to 0x3
if (!ClientUtils.IsEnumValid(value, (int)value, (int)LinkBehavior.SystemDefault, (int)LinkBehavior.NeverUnderline)){
throw new InvalidEnumArgumentException("LinkBehavior", (int)value, typeof(LinkBehavior));
}
if (value != linkBehavior) {
linkBehavior = value;
InvalidateLinkFonts();
InvalidateLink(null);
}
}
}
///
///
/// Gets or sets the color used to display links in normal cases.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelLinkColorDescr)
]
public Color LinkColor {
get {
if (linkColor.IsEmpty) {
return IELinkColor;
}
else {
return linkColor;
}
}
set {
if (linkColor != value) {
linkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Gets the collection of links used in a
///
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public LinkCollection Links {
get {
if (linkCollection == null) {
linkCollection = new LinkCollection(this);
}
return linkCollection;
}
}
///
///
/// Gets or sets a value indicating whether the link should be displayed as if it was visited.
///
///
[
DefaultValue(false),
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelLinkVisitedDescr)
]
public bool LinkVisited {
get {
if (links.Count == 0) {
return false;
}
else {
return((Link)links[0]).Visited;
}
}
set {
if (value != LinkVisited) {
if (links.Count == 0) {
Links.Add(new Link(this));
}
((Link)links[0]).Visited = value;
}
}
}
// link labels must always ownerdraw
//
internal override bool OwnerDraw {
get {
return true;
}
}
///
/// [To be supplied.]
///
protected Cursor OverrideCursor {
get {
return overrideCursor;
}
set {
if (overrideCursor != value) {
overrideCursor = value;
if (IsHandleCreated) {
// We want to instantly change the cursor if the mouse is within our bounds.
// This includes the case where the mouse is over one of our children
NativeMethods.POINT p = new NativeMethods.POINT();
NativeMethods.RECT r = new NativeMethods.RECT();
UnsafeNativeMethods.GetCursorPos(p);
UnsafeNativeMethods.GetWindowRect(new HandleRef(this, Handle), ref r);
//
if ((r.left <= p.x && p.x < r.right && r.top <= p.y && p.y < r.bottom) || UnsafeNativeMethods.GetCapture() == Handle)
SendMessage(NativeMethods.WM_SETCURSOR, Handle, NativeMethods.HTCLIENT);
}
}
}
}
///
///
/// Gets or sets the color used to display the link once it has been visited.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelVisitedLinkColorDescr)
]
public Color VisitedLinkColor {
get {
if (visitedLinkColor.IsEmpty) {
return IEVisitedLinkColor;
}
else {
return visitedLinkColor;
}
}
set {
if (visitedLinkColor != value) {
visitedLinkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Occurs when the link is clicked.
///
///
[WinCategory("Action"), SRDescription(SR.LinkLabelLinkClickedDescr)]
public event LinkLabelLinkClickedEventHandler LinkClicked {
add {
Events.AddHandler(EventLinkClicked, value);
}
remove {
Events.RemoveHandler(EventLinkClicked, value);
}
}
internal static Rectangle CalcTextRenderBounds(Rectangle textRect, Rectangle clientRect, ContentAlignment align) {
int xLoc, yLoc, width, height;
if ((align & WindowsFormsUtils.AnyRightAlign) != 0) {
xLoc = clientRect.Right - textRect.Width;
} else if ((align & WindowsFormsUtils.AnyCenterAlign) != 0) {
xLoc = (clientRect.Width - textRect.Width) / 2;
} else {
xLoc = clientRect.X;
}
if ((align & WindowsFormsUtils.AnyBottomAlign) != 0) {
yLoc = clientRect.Bottom - textRect.Height;
} else if ((align & WindowsFormsUtils.AnyMiddleAlign) != 0) {
yLoc = (clientRect.Height - textRect.Height) / 2;
} else {
yLoc = clientRect.Y;
}
// If the text rect does not fit in the client rect, make it fit.
if (textRect.Width > clientRect.Width) {
xLoc = clientRect.X;
width = clientRect.Width;
} else {
width = textRect.Width;
}
if (textRect.Height > clientRect.Height) {
yLoc = clientRect.Y;
height = clientRect.Height;
} else {
height = textRect.Height;
}
return new Rectangle(xLoc, yLoc, width, height);
}
///
/// Constructs the new instance of the accessibility object for this control. Subclasses
/// should not call base.CreateAccessibilityObject.
///
protected override AccessibleObject CreateAccessibilityInstance() {
return new LinkLabelAccessibleObject(this);
}
///
///
/// Creates a handle for this control. This method is called by the .NET Framework,
/// this should not be called. Inheriting classes should always call
/// base.createHandle when overriding this method.
///
///
protected override void CreateHandle() {
base.CreateHandle();
InvalidateTextLayout();
}
///
/// Determines whether the current state of the control allows for rendering text using
/// TextRenderer (GDI).
/// The Gdi library doesn't currently have a way to calculate character ranges so we cannot
/// use it for painting link(s) within the text, but if the link are is null or covers the
/// entire text we are ok since it is just one area with the same size of the text binding
/// area.
///
internal override bool CanUseTextRenderer {
get{
// If no link or the LinkArea is one and covers the entire text, we can support UseCompatibleTextRendering = false.
// Observe that LinkArea refers to the first link always.
StringInfo stringInfo = new StringInfo( this.Text );
return this.LinkArea.Start == 0 && ( this.LinkArea.Length == 0 || this.LinkArea.Length == stringInfo.LengthInTextElements );
}
}
internal override bool UseGDIMeasuring() {
return !UseCompatibleTextRendering;
}
///
/// Converts the character index into char index of the string
/// This method is copied in LinkCollectionEditor.cs. Update the other
/// one as well if you change this method.
/// This method mainly deal with surrogate. Suppose we
/// have a string consisting of 3 surrogates, and we want the
/// second character, then the index we need should be 2 instead of
/// 1, and this method returns the correct index.
///
private static int ConvertToCharIndex(int index, string text) {
if (index <= 0) {
return 0;
}
if (String.IsNullOrEmpty(text)) {
Debug.Assert(text != null, "string should not be null");
//do no conversion, just return the original value passed in
return index;
}
//VSWhidbey 217272: Dealing with surrogate characters
//in some languages, characters can expand over multiple
//chars, using StringInfo lets us properly deal with it.
StringInfo stringInfo = new StringInfo(text);
int numTextElements = stringInfo.LengthInTextElements;
//index is greater than the length of the string
if (index > numTextElements) {
return index - numTextElements + text.Length; //pretend all the characters after are ASCII characters
}
//return the length of the substring which has specified number of characters
string sub = stringInfo.SubstringByTextElements(0, index);
return sub.Length;
}
///
/// Ensures that we have analyzed the text run so that we can render each segment
/// and link.
///
private void EnsureRun(Graphics g) {
// bail early if everything is valid!
//
if (textLayoutValid) {
return;
}
if (this.textRegion != null) {
this.textRegion.Dispose();
this.textRegion = null;
}
// bail early for no text
//
if (Text.Length == 0) {
Links.Clear();
Links.Add (new Link (0, -1)); // default 'magic' link.
textLayoutValid = true;
return;
}
StringFormat textFormat = CreateStringFormat();
string text = Text;
try {
Font alwaysUnderlined = new Font(Font, Font.Style | FontStyle.Underline);
Graphics created = null;
try {
if (g == null) {
g = created = CreateGraphicsInternal();
}
if( UseCompatibleTextRendering ){
Region[] textRegions = g.MeasureCharacterRanges (text, alwaysUnderlined, ClientRectWithPadding, textFormat);
int regionIndex = 0;
for (int i=0; i
/// Calculate character ranges taking into account the locale. Provided for surrogate chars support.
///
private CharacterRange[] AdjustCharacterRangesForSurrogateChars(){
string text = Text;
if (String.IsNullOrEmpty(text)) {
return new CharacterRange[]{};
}
StringInfo stringInfo = new StringInfo(text);
int textLen = stringInfo.LengthInTextElements;
ArrayList ranges = new ArrayList(Links.Count);
foreach (Link link in Links) {
int charStart = ConvertToCharIndex(link.Start, text);
int charEnd = ConvertToCharIndex(link.Start + link.Length, text);
if (LinkInText(charStart, charEnd - charStart)) {
int length = (int) Math.Min(link.Length, textLen - link.Start);
ranges.Add(new CharacterRange(charStart, ConvertToCharIndex(link.Start + length, text) - charStart));
}
}
CharacterRange[] regions = new CharacterRange[ranges.Count + 1];
ranges.CopyTo(regions, 0);
regions[regions.Length - 1] = new CharacterRange(0, text.Length);
return regions;
}
///
/// Determines whether the whole link label contains only one link,
/// and the link runs from the beginning of the label to the end of it
///
private bool IsOneLink() {
if (links == null || links.Count != 1 || Text == null) {
return false;
}
StringInfo stringInfo = new StringInfo(Text);
if (LinkArea.Start == 0 && LinkArea.Length == stringInfo.LengthInTextElements) {
return true;
}
return false;
}
///
/// Determines if the given client coordinates is contained within a portion
/// of a link area.
///
protected Link PointInLink(int x, int y) {
Graphics g = CreateGraphicsInternal();
Link hit = null;
try {
EnsureRun(g);
foreach (Link link in links) {
if (link.VisualRegion != null && link.VisualRegion.IsVisible(x, y, g)) {
hit = link;
break;
}
}
}
finally {
g.Dispose();
g = null;
}
return hit;
}
///
/// Invalidates only the portions of the text that is linked to
/// the specified link. If link is null, then all linked text
/// is invalidated.
///
private void InvalidateLink(Link link) {
if (IsHandleCreated) {
if (link == null || link.VisualRegion == null || IsOneLink()) {
Invalidate();
}
else{
Invalidate(link.VisualRegion);
}
}
}
///
/// Invalidates the current set of fonts we use when painting
/// links. The fonts will be recreated when needed.
///
private void InvalidateLinkFonts() {
if (linkFont != null) {
linkFont.Dispose();
}
if (hoverLinkFont != null && hoverLinkFont != linkFont) {
hoverLinkFont.Dispose();
}
linkFont = null;
hoverLinkFont = null;
}
private void InvalidateTextLayout() {
textLayoutValid = false;
}
private bool LinkInText(int start, int length) {
return(0 <= start && start < Text.Length && 0 < length);
}
///
///
/// Gets or sets a value that is returned to the
/// parent form when the link label.
/// is clicked.
///
///
DialogResult IButtonControl.DialogResult {
get {
return dialogResult;
}
set {
//valid values are 0x0 to 0x7
if (!ClientUtils.IsEnumValid(value, (int)value, (int)DialogResult.None, (int)DialogResult.No))
{
throw new InvalidEnumArgumentException("value", (int)value, typeof(DialogResult));
}
dialogResult = value;
}
}
///
///
/// Raises the
///
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Security", "CA2106:SecureAsserts")]
protected override void OnGotFocus(EventArgs e) {
if (!this.processingOnGotFocus) {
base.OnGotFocus(e);
this.processingOnGotFocus = true;
}
try {
Link focusLink = FocusLink;
if (focusLink == null) {
// SECREVIEW: This assert is required because the call to Select will generate a call to SetActiveControl which have a demand,
// it is safe since no input from user code is processed while setting the active control originated this way.
//
IntSecurity.ModifyFocus.Assert();
// Set focus on first link.
// This will raise the OnGotFocus event again but it will not be processed because processingOnGotFocus is true.
Select(true /*directed*/, true /*forward*/);
}
else {
InvalidateLink(focusLink);
UpdateAccessibilityLink(focusLink);
}
}
finally {
if (this.processingOnGotFocus) {
this.processingOnGotFocus = false;
}
}
}
///
///
/// Raises the
///
protected override void OnLostFocus(EventArgs e) {
base.OnLostFocus(e);
if (FocusLink != null) {
InvalidateLink(FocusLink);
}
}
///
///
/// Raises the
///
protected override void OnKeyDown(KeyEventArgs e) {
base.OnKeyDown(e);
if (e.KeyCode == Keys.Enter) {
if (FocusLink != null && FocusLink.Enabled) {
OnLinkClicked(new LinkLabelLinkClickedEventArgs(FocusLink));
}
}
}
///
///
/// Raises the
///
protected override void OnMouseLeave(EventArgs e) {
base.OnMouseLeave(e);
if (!Enabled) {
return;
}
foreach (Link link in links) {
if ((link.State & LinkState.Hover) == LinkState.Hover
|| (link.State & LinkState.Active) == LinkState.Active) {
bool activeChanged = (link.State & LinkState.Active) == LinkState.Active;
link.State &= ~(LinkState.Hover | LinkState.Active);
if (activeChanged || hoverLinkFont != linkFont) {
InvalidateLink(link);
}
OverrideCursor = null;
}
}
}
///
///
/// Raises the
///
protected override void OnMouseDown(MouseEventArgs e) {
base.OnMouseDown(e);
if (!Enabled || e.Clicks > 1) {
receivedDoubleClick = true;
return;
}
for (int i=0; i
///
/// Raises the
///
protected override void OnMouseUp(MouseEventArgs e) {
base.OnMouseUp(e);
// bug 95211 : don't do any Handle-related operations when in disposing state
if (Disposing || IsDisposed) {
return;
}
if (!Enabled || e.Clicks > 1 || receivedDoubleClick) {
receivedDoubleClick = false;
return;
}
for (int i=0; i
///
/// Raises the
///
protected override void OnMouseMove(MouseEventArgs e) {
base.OnMouseMove(e);
if (!Enabled) {
return;
}
Link hoverLink = null;
foreach (Link link in links) {
if ((link.State & LinkState.Hover) == LinkState.Hover) {
hoverLink = link;
break;
}
}
Link pointIn = PointInLink(e.X, e.Y);
if (pointIn != hoverLink) {
if (hoverLink != null) {
hoverLink.State &= ~LinkState.Hover;
}
if (pointIn != null) {
pointIn.State |= LinkState.Hover;
if (pointIn.Enabled) {
OverrideCursor = Cursors.Hand;
}
}
else {
OverrideCursor = null;
}
if (hoverLinkFont != linkFont) {
if (hoverLink != null) {
InvalidateLink(hoverLink);
}
if (pointIn != null) {
InvalidateLink(pointIn);
}
}
}
}
///
///
/// Raises the
///
protected virtual void OnLinkClicked(LinkLabelLinkClickedEventArgs e) {
LinkLabelLinkClickedEventHandler handler = (LinkLabelLinkClickedEventHandler)Events[EventLinkClicked];
if (handler != null) {
handler(this, e);
}
}
protected override void OnPaddingChanged(EventArgs e) {
base.OnPaddingChanged(e);
InvalidateTextLayout();
}
///
///
/// Raises the
///
protected override void OnPaint(PaintEventArgs e) {
RectangleF finalrect = RectangleF.Empty; //the focus rectangle if there is only one link
Animate();
ImageAnimator.UpdateFrames();
EnsureRun(e.Graphics);
// bail early for no text
//
if (Text.Length == 0) {
PaintLinkBackground(e.Graphics);
}
// Paint enabled link label
//
else {
if (AutoEllipsis) {
Rectangle clientRect = this.ClientRectWithPadding;
Size preferredSize = GetPreferredSize(new Size(clientRect.Width, clientRect.Height));
showToolTip = (clientRect.Width < preferredSize.Width || clientRect.Height < preferredSize.Height);
}
else {
showToolTip = false;
}
if (this.Enabled) { // Control.Enabled not to be confused with Link.Enabled
bool optimizeBackgroundRendering = !GetStyle(ControlStyles.OptimizedDoubleBuffer);
SolidBrush foreBrush = new SolidBrush(ForeColor);
SolidBrush linkBrush = new SolidBrush(LinkColor);
try {
if (!optimizeBackgroundRendering) {
PaintLinkBackground(e.Graphics);
}
LinkUtilities.EnsureLinkFonts(this.Font, this.LinkBehavior, ref this.linkFont, ref this.hoverLinkFont);
Region originalClip = e.Graphics.Clip;
try {
if (IsOneLink()) {
//exclude the area to draw the focus rectangle
e.Graphics.Clip = originalClip;
RectangleF[] rects = ((Link)links[0]).VisualRegion.GetRegionScans(e.Graphics.Transform);
if (rects != null && rects.Length > 0) {
if (UseCompatibleTextRendering) {
finalrect = new RectangleF(rects[0].Location, SizeF.Empty);
foreach (RectangleF rect in rects) {
finalrect = RectangleF.Union(finalrect, rect);
}
}
else {
finalrect = this.ClientRectWithPadding;
Size finalRectSize = finalrect.Size.ToSize();
Size requiredSize = MeasureTextCache.GetTextSize(Text, Font, finalRectSize, CreateTextFormatFlags(finalRectSize));
finalrect.Width = requiredSize.Width;
if (requiredSize.Height < finalrect.Height) {
finalrect.Height = requiredSize.Height;
}
finalrect = CalcTextRenderBounds(System.Drawing.Rectangle.Round(finalrect) /*textRect*/, this.ClientRectWithPadding /*clientRect*/, RtlTranslateContent(this.TextAlign));
}
e.Graphics.ExcludeClip(new Region(finalrect));
}
}
else {
foreach (Link link in links) {
if (link.VisualRegion != null) {
e.Graphics.ExcludeClip(link.VisualRegion);
}
}
}
PaintLink(e.Graphics, null, foreBrush, linkBrush, optimizeBackgroundRendering, finalrect);
foreach (Link link in links) {
PaintLink(e.Graphics, link, foreBrush, linkBrush, optimizeBackgroundRendering, finalrect);
}
if (optimizeBackgroundRendering) {
e.Graphics.Clip = originalClip;
e.Graphics.ExcludeClip(this.textRegion);
PaintLinkBackground(e.Graphics);
}
}
finally {
e.Graphics.Clip = originalClip;
}
}
finally {
foreBrush.Dispose();
linkBrush.Dispose();
}
}
// Paint disabled link label (disabled control, not to be confused with disabled link).
//
else {
Region originalClip = e.Graphics.Clip;
try {
// We need to paint the background first before clipping to textRegion because it is calculated using
// ClientRectWithPadding which in some cases is smaller that ClientRectangle.
//
PaintLinkBackground(e.Graphics);
e.Graphics.IntersectClip(this.textRegion);
Color foreColor;
if (UseCompatibleTextRendering) {
// APPCOMPAT: Use DisabledColor because Everett used DisabledColor.
// (ie, dont use Graphics.GetNearestColor(DisabledColor.)
// vsw 495322.
StringFormat stringFormat = CreateStringFormat();
ControlPaint.DrawStringDisabled(e.Graphics, Text, Font, DisabledColor, ClientRectWithPadding, stringFormat);
}
else {
IntPtr hdc = e.Graphics.GetHdc();
try {
using (WindowsGraphics wg = WindowsGraphics.FromHdc(hdc)) {
foreColor = wg.GetNearestColor(DisabledColor);
}
}
finally {
e.Graphics.ReleaseHdc();
}
Rectangle clientRectWidthPadding = ClientRectWithPadding;
ControlPaint.DrawStringDisabled(e.Graphics, Text, Font, foreColor, clientRectWidthPadding, CreateTextFormatFlags(clientRectWidthPadding.Size));
}
}
finally {
e.Graphics.Clip = originalClip;
}
}
}
// We can't call base.OnPaint because labels paint differently from link labels,
// but we still need to raise the Paint event.
//
RaisePaintEvent(this, e);
}
///
/// [To be supplied.]
///
protected override void OnPaintBackground(PaintEventArgs e) {
Image i = this.Image;
if (i != null) {
Region oldClip = e.Graphics.Clip;
Rectangle imageBounds = CalcImageRenderBounds(i, ClientRectangle, RtlTranslateAlignment(ImageAlign));
e.Graphics.ExcludeClip(imageBounds);
try {
base.OnPaintBackground(e);
}
finally {
e.Graphics.Clip = oldClip;
}
e.Graphics.IntersectClip(imageBounds);
try {
base.OnPaintBackground(e);
DrawImage(e.Graphics, i, ClientRectangle, RtlTranslateAlignment(ImageAlign));
}
finally {
e.Graphics.Clip = oldClip;
}
}
else {
base.OnPaintBackground(e);
}
}
///
/// [To be supplied.]
///
protected override void OnFontChanged(EventArgs e) {
base.OnFontChanged(e);
InvalidateTextLayout();
InvalidateLinkFonts();
Invalidate();
}
///
///
protected override void OnAutoSizeChanged(EventArgs e) {
base.OnAutoSizeChanged(e);
InvalidateTextLayout();
}
///
/// Overriden by LinkLabel.
///
internal override void OnAutoEllipsisChanged(/*EventArgs e*/) {
base.OnAutoEllipsisChanged(/*e*/);
InvalidateTextLayout();
}
///
/// [To be supplied.]
///
protected override void OnEnabledChanged(EventArgs e) {
base.OnEnabledChanged(e);
if (!Enabled) {
for (int i=0; i
/// [To be supplied.]
///
protected override void OnTextChanged(EventArgs e) {
base.OnTextChanged(e);
InvalidateTextLayout();
UpdateSelectability();
}
///
/// [To be supplied.]
///
protected override void OnTextAlignChanged(EventArgs e) {
base.OnTextAlignChanged(e);
InvalidateTextLayout();
UpdateSelectability();
}
private void PaintLink(Graphics g, Link link, SolidBrush foreBrush, SolidBrush linkBrush, bool optimizeBackgroundRendering, RectangleF finalrect) {
// link = null means paint the whole text
Debug.Assert(g != null, "Must pass valid graphics");
Debug.Assert(foreBrush != null, "Must pass valid foreBrush");
Debug.Assert(linkBrush != null, "Must pass valid linkBrush");
Font font = Font;
if (link != null) {
if (link.VisualRegion != null) {
Color brushColor = Color.Empty;
LinkState linkState = link.State;
if ((linkState & LinkState.Hover) == LinkState.Hover) {
font = hoverLinkFont;
}
else {
font = linkFont;
}
if (link.Enabled) { // Not to be confused with Control.Enabled.
if ((linkState & LinkState.Active) == LinkState.Active) {
brushColor = ActiveLinkColor;
}
else if ((linkState & LinkState.Visited) == LinkState.Visited) {
brushColor = VisitedLinkColor;
}
// else use linkBrush
}
else {
brushColor = DisabledLinkColor;
}
if (IsOneLink()) {
g.Clip = new Region(finalrect);
}
else {
g.Clip = link.VisualRegion;
}
if (optimizeBackgroundRendering) {
PaintLinkBackground(g);
}
if( UseCompatibleTextRendering ){
SolidBrush useBrush = brushColor == Color.Empty ? linkBrush : new SolidBrush( brushColor );
StringFormat stringFormat = CreateStringFormat();
g.DrawString(Text, font, useBrush, ClientRectWithPadding, stringFormat);
if( useBrush != linkBrush ){
useBrush.Dispose();
}
}
else{
if(brushColor == Color.Empty ){
brushColor = linkBrush.Color;
}
IntPtr hdc = g.GetHdc();
try{
using( WindowsGraphics wg = WindowsGraphics.FromHdc( hdc ) ) {
brushColor = wg.GetNearestColor(brushColor);
}
}
finally{
g.ReleaseHdc();
}
Rectangle clientRectWithPadding = ClientRectWithPadding;
TextRenderer.DrawText(g, Text, font, clientRectWithPadding, brushColor, CreateTextFormatFlags(clientRectWithPadding.Size));
}
if (Focused && ShowFocusCues && FocusLink == link) {
// Get the rectangles making up the visual region, and draw
// each one.
RectangleF[] rects = link.VisualRegion.GetRegionScans(g.Transform);
if( rects != null && rects.Length > 0 ){
Rectangle focusRect;
if (IsOneLink()) {
//draw one merged focus rectangle
focusRect = Rectangle.Ceiling(finalrect);
Debug.Assert(finalrect != RectangleF.Empty, "finalrect should be initialized");
ControlPaint.DrawFocusRectangle(g, focusRect, ForeColor, BackColor);
}
else {
foreach (RectangleF rect in rects) {
ControlPaint.DrawFocusRectangle(g, Rectangle.Ceiling(rect), ForeColor, BackColor);
}
}
}
}
}
// no else clause... we don't paint anything if we are given a link with no visual region.
//
}
else { // Painting with no link.
g.IntersectClip(this.textRegion);
if (optimizeBackgroundRendering) {
PaintLinkBackground(g);
}
if( UseCompatibleTextRendering ){
StringFormat stringFormat = CreateStringFormat();
g.DrawString(Text, font, foreBrush, ClientRectWithPadding, stringFormat);
}
else{
Color color;
IntPtr hdc = g.GetHdc();
try{
using( WindowsGraphics wg = WindowsGraphics.FromHdc( hdc ) ) {
color = wg.GetNearestColor(foreBrush.Color);
}
}
finally{
g.ReleaseHdc();
}
Rectangle clientRectWithPadding = ClientRectWithPadding;
TextRenderer.DrawText(g, Text, font, clientRectWithPadding, color, CreateTextFormatFlags(clientRectWithPadding.Size));
}
}
}
private void PaintLinkBackground(Graphics g) {
using (PaintEventArgs e = new PaintEventArgs(g, ClientRectangle)) {
InvokePaintBackground(this, e);
}
}
///
///
/// Processes a dialog key. This method is called during message pre-processing
/// to handle dialog characters, such as TAB, RETURN, ESCAPE, and arrow keys. This
/// method is called only if the isInputKey() method indicates that the control
/// isn't interested in the key. processDialogKey() simply sends the character to
/// the parent's processDialogKey() method, or returns false if the control has no
/// parent. The Form class overrides this method to perform actual processing
/// of dialog keys. When overriding processDialogKey(), a control should return true
/// to indicate that it has processed the key. For keys that aren't processed by the
/// control, the result of "base.processDialogChar()" should be returned. Controls
/// will seldom, if ever, need to override this method.
///
///
[UIPermission(SecurityAction.LinkDemand, Window=UIPermissionWindow.AllWindows)]
protected override bool ProcessDialogKey(Keys keyData) {
if ((keyData & (Keys.Alt | Keys.Control)) != Keys.Alt) {
Keys keyCode = keyData & Keys.KeyCode;
switch (keyCode) {
case Keys.Tab:
if (TabStop) {
bool forward = (keyData & Keys.Shift) != Keys.Shift;
if (FocusNextLink(forward)) {
return true;
}
}
break;
case Keys.Up:
case Keys.Left:
if (FocusNextLink(false)) {
return true;
}
break;
case Keys.Down:
case Keys.Right:
if (FocusNextLink(true)) {
return true;
}
break;
}
}
return base.ProcessDialogKey(keyData);
}
private bool FocusNextLink(bool forward) {
int focusIndex = -1;
if (focusLink != null) {
for (int i=0; i= 0) {
test = Links[focusIndex];
charStart = ConvertToCharIndex(test.Start, text);
charEnd = ConvertToCharIndex(test.Start + test.Length, text);
}
else {
test = null;
}
} while (test != null
&& !test.Enabled
&& LinkInText(charStart, charEnd - charStart));
}
if (focusIndex < 0 || focusIndex >= links.Count) {
return -1;
}
else {
return focusIndex;
}
}
private void ResetLinkArea() {
LinkArea = new LinkArea(0, -1);
}
internal void ResetActiveLinkColor() {
activeLinkColor = Color.Empty;
}
internal void ResetDisabledLinkColor() {
disabledLinkColor = Color.Empty;
}
internal void ResetLinkColor() {
linkColor = Color.Empty;
InvalidateLink(null);
}
private void ResetVisitedLinkColor() {
visitedLinkColor = Color.Empty;
}
///
///
/// Performs the work of setting the bounds of this control. Inheriting classes
/// can overide this function to add size restrictions. Inheriting classes must call
/// base.setBoundsCore to actually cause the bounds of the control to change.
///
///
protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified) {
// we cache too much state to try and optimize this (regions, etc)... it is best
// to always relayout here... If we want to resurect this code in the future,
// remember that we need to handle a word wrapped top aligned text that
// will become newly exposed (and therefore layed out) when we resize...
//
/*
ContentAlignment anyTop = ContentAlignment.TopLeft | ContentAlignment.TopCenter | ContentAlignment.TopRight;
if ((TextAlign & anyTop) == 0 || Width != width || (Image != null && (ImageAlign & anyTop) == 0)) {
InvalidateTextLayout();
Invalidate();
}
*/
InvalidateTextLayout();
Invalidate();
base.SetBoundsCore(x, y, width, height, specified);
}
///
/// [To be supplied.]
///
protected override void Select(bool directed, bool forward) {
if (directed) {
// In a multi-link label, if the tab came from another control, we want to keep the currently
// focused link, otherwise, we set the focus to the next link.
if (links.Count > 0) {
// Find which link is currently focused
//
int focusIndex = -1;
if (FocusLink != null) {
focusIndex = links.IndexOf(FocusLink);
}
// We could be getting focus from ourself, so we must
// invalidate each time.
//
FocusLink = null;
int newFocus = GetNextLinkIndex(focusIndex, forward);
if (newFocus == -1) {
if (forward) {
newFocus = GetNextLinkIndex(-1, forward); // -1, so "next" will be 0
}
else {
newFocus = GetNextLinkIndex(links.Count, forward); // Count, so "next" will be Count-1
}
}
if (newFocus != -1) {
FocusLink = (Link)links[newFocus];
}
}
}
base.Select(directed, forward);
}
///
///
/// Determines if the color for active links should remain the same.
///
///
internal bool ShouldSerializeActiveLinkColor() {
return !activeLinkColor.IsEmpty;
}
///
///
/// Determines if the color for disabled links should remain the same.
///
///
internal bool ShouldSerializeDisabledLinkColor() {
return !disabledLinkColor.IsEmpty;
}
///
///
/// Determines if the range in text that is treated as a
/// link should remain the same.
///
///
private bool ShouldSerializeLinkArea() {
if (links.Count == 1) {
// use field access to find out if "length" is really -1
return Links[0].Start != 0 || Links[0].length != -1;
}
return true;
}
///
///
/// Determines if the color of links in normal cases should remain the same.
///
///
internal bool ShouldSerializeLinkColor() {
return !linkColor.IsEmpty;
}
///
/// Determines whether designer should generate code for setting the UseCompatibleTextRendering or not.
/// DefaultValue(false)
///
private bool ShouldSerializeUseCompatibleTextRendering() {
// Serialize code if LinkLabel cannot support the feature or the property's value is not the default.
return !CanUseTextRenderer || UseCompatibleTextRendering != Control.UseCompatibleTextRenderingDefault;
}
///
///
/// Determines if the color of links that have been visited should remain the same.
///
///
private bool ShouldSerializeVisitedLinkColor() {
return !visitedLinkColor.IsEmpty;
}
///
///
/// Update accessibility with the currently focused link.
///
///
private void UpdateAccessibilityLink(Link focusLink) {
if (!IsHandleCreated) {
return;
}
int focusIndex = -1;
for (int i=0; i
/// Validates that no links overlap. This will throw an exception if
/// they do.
///
private void ValidateNoOverlappingLinks() {
for (int x=0; x
/// Updates the label's ability to get focus. If there are
/// any links in the label, then the label can get focus,
/// else it can't.
///
private void UpdateSelectability() {
LinkArea pt = LinkArea;
bool selectable = false;
string text = Text;
int charStart = ConvertToCharIndex(pt.Start, text);
int charEnd = ConvertToCharIndex(pt.Start + pt.Length, text);
if (LinkInText(charStart, charEnd - charStart)) {
selectable = true;
}
else {
// If a link is currently focused, de-select it
//
if (FocusLink != null) {
FocusLink = null;
}
}
OverrideCursor = null;
TabStop = selectable;
SetStyle(ControlStyles.Selectable, selectable);
}
///
/// Determines whether to use compatible text rendering engine (GDI+) or not (GDI).
///
[
// DefaultValue(false), - // See ShouldSerailizeUseCompatibleTextRendering method.
RefreshProperties(RefreshProperties.Repaint),
SRCategory(SR.CatBehavior),
SRDescription(SR.UseCompatibleTextRenderingDescr)
]
public new bool UseCompatibleTextRendering {
get {
Debug.Assert( CanUseTextRenderer || base.UseCompatibleTextRendering, "Using GDI text rendering when CanUseTextRenderer reported false." );
return base.UseCompatibleTextRendering;
}
set {
if (base.UseCompatibleTextRendering != value) {
// Cache the value so it is restored if CanUseTextRenderer becomes true and the designer can undo changes to this as side effect.
base.UseCompatibleTextRendering = value;
InvalidateTextLayout();
}
}
}
///
/// Handles the WM_SETCURSOR message
///
///
///
[SecurityPermission(SecurityAction.LinkDemand, Flags=SecurityPermissionFlag.UnmanagedCode)]
protected override void WndProc(ref Message msg) {
switch (msg.Msg) {
case NativeMethods.WM_SETCURSOR:
WmSetCursor(ref msg);
break;
default:
base.WndProc(ref msg);
break;
}
}
///
/// [To be supplied.]
///
public class LinkCollection : IList {
private LinkLabel owner;
private bool linksAdded = false; //whether we should serialize the linkCollection
/// A caching mechanism for key accessor
/// We use an index here rather than control so that we don't have lifetime
/// issues by holding on to extra references.
/// Note this is not Thread Safe - but Winforms has to be run in a STA anyways.
private int lastAccessedIndex = -1;
///
/// [To be supplied.]
///
public LinkCollection(LinkLabel owner) {
if (owner == null)
throw new ArgumentNullException("owner");
this.owner = owner;
}
///
/// [To be supplied.]
///
public virtual Link this[int index] {
get {
return(Link)owner.links[index];
}
set {
owner.links[index] = value;
owner.links.Sort(LinkLabel.linkComparer);
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
///
/// Retrieves the child control with the specified key.
///
public virtual Link this[string key] {
get {
// We do not support null and empty string as valid keys.
if (string.IsNullOrEmpty(key)){
return null;
}
// Search for the key in our collection
int index = IndexOfKey(key);
if (IsValidIndex(index)) {
return this[index];
}
else {
return null;
}
}
}
///
/// [To be supplied.]
///
[Browsable(false)]
public int Count {
get {
return owner.links.Count;
}
}
///
/// whether we have added a non-trivial link to the collection
///
public bool LinksAdded {
get {
return linksAdded;
}
}
///
/// [To be supplied.]
///
public bool IsReadOnly {
get {
return false;
}
}
///
/// [To be supplied.]
///
public Link Add(int start, int length) {
if (length != 0) {
linksAdded = true;
}
return Add(start, length, null);
}
///
/// [To be supplied.]
///
public Link Add(int start, int length, object linkData) {
if (length != 0) {
linksAdded = true;
}
// check for the special case where the list is in the "magic"
// state of having only the default link in it. In that case
// we want to clear the list before adding this link.
//
if (owner.links.Count == 1
&& this[0].Start == 0
&& this[0].length == -1) {
owner.links.Clear();
}
Link l = new Link(owner);
l.Start = start;
l.Length = length;
l.LinkData = linkData;
Add(l);
return l;
}
///
/// [To be supplied.]
///
public int Add(Link value) {
if (value != null && value.Length != 0) {
linksAdded = true;
}
// check for the special case where the list is in the "magic"
// state of having only the default link in it. In that case
// we want to clear the list before adding this link.
//
if (owner.links.Count == 1
&& this[0].Start == 0
&& this[0].length == -1) {
owner.links.Clear();
}
// Set the owner control for this link
value.Owner = this.owner;
owner.links.Add(value);
if (this.owner.AutoSize) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
if (owner.Links.Count > 1) {
owner.links.Sort(LinkLabel.linkComparer);
}
owner.ValidateNoOverlappingLinks();
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
if (owner.Links.Count > 1) {
return IndexOf(value);
}
else {
return 0;
}
}
///
/// [To be supplied.]
///
public bool Contains(Link link) {
return owner.links.Contains(link);
}
///
/// Returns true if the collection contains an item with the specified key, false otherwise.
///
public virtual bool ContainsKey(string key) {
return IsValidIndex(IndexOfKey(key));
}
///
/// [To be supplied.]
///
public int IndexOf(Link link) {
return owner.links.IndexOf(link);
}
///
/// The zero-based index of the first occurrence of value within the entire CollectionBase, if found; otherwise, -1.
///
public virtual int IndexOfKey(String key) {
// Step 0 - Arg validation
if (string.IsNullOrEmpty(key)){
return -1; // we dont support empty or null keys.
}
// step 1 - check the last cached item
if (IsValidIndex(lastAccessedIndex))
{
if (WindowsFormsUtils.SafeCompareStrings(this[lastAccessedIndex].Name, key, /* ignoreCase = */ true)) {
return lastAccessedIndex;
}
}
// step 2 - search for the item
for (int i = 0; i < this.Count; i ++) {
if (WindowsFormsUtils.SafeCompareStrings(this[i].Name, key, /* ignoreCase = */ true)) {
lastAccessedIndex = i;
return i;
}
}
// step 3 - we didn't find it. Invalidate the last accessed index and return -1.
lastAccessedIndex = -1;
return -1;
}
///
/// Determines if the index is valid for the collection.
///
///
/// Remove all links from the linkLabel.
///
public virtual void Clear() {
bool doLayout = this.owner.links.Count > 0 && this.owner.AutoSize;
owner.links.Clear();
if (doLayout) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
}
///
/// [To be supplied.]
///
public IEnumerator GetEnumerator() {
if (owner.links != null) {
return owner.links.GetEnumerator();
}
else {
return new Link[0].GetEnumerator();
}
}
///
/// [To be supplied.]
///
public void Remove(Link value) {
if (value.Owner != this.owner) {
return;
}
owner.links.Remove(value);
if (this.owner.AutoSize) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
owner.links.Sort(LinkLabel.linkComparer);
owner.ValidateNoOverlappingLinks();
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
if (owner.FocusLink == null && owner.links.Count > 0) {
owner.FocusLink = (Link)owner.links[0];
}
}
///
/// [To be supplied.]
///
public void RemoveAt(int index) {
Remove(this[index]);
}
///
/// Removes the child control with the specified key.
///
public virtual void RemoveByKey(string key) {
int index = IndexOfKey(key);
if (IsValidIndex(index)) {
RemoveAt(index);
}
}
///
/// [To be supplied.]
///
[
TypeConverter(typeof(LinkConverter))
]
public class Link {
private int start = 0;
private object linkData = null;
private LinkState state = LinkState.Normal;
private bool enabled = true;
private Region visualRegion;
internal int length = 0;
private LinkLabel owner = null;
private string name = null;
private string description = null;
private object userData;
///
/// Description for accessibility
///
public string Description {
get {
return description;
}
set {
description = value;
}
}
///
/// [To be supplied.]
///
[DefaultValue(true)]
public bool Enabled {
get {
return enabled;
}
set {
if (enabled != value) {
enabled = value;
if ((int)(state & (LinkState.Hover | LinkState.Active)) != 0) {
state &= ~(LinkState.Hover | LinkState.Active);
if (owner != null) {
owner.OverrideCursor = null;
}
}
if (owner != null) {
owner.InvalidateLink(this);
}
}
}
}
///
/// [To be supplied.]
///
public int Length {
get {
if (length == -1) {
if (owner != null && !String.IsNullOrEmpty(owner.Text)) {
StringInfo stringInfo = new StringInfo(owner.Text);
return stringInfo.LengthInTextElements - Start;
}
else {
return 0;
}
}
return length;
}
set {
if (length != value) {
length = value;
if (owner != null) {
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
}
}
///
/// [To be supplied.]
///
[DefaultValue(null)]
public object LinkData {
get {
return linkData;
}
set {
linkData = value;
}
}
///
/// The LinkLabel object that owns this link.
///
internal LinkLabel Owner {
get {
return owner;
}
set {
owner = value;
}
}
internal LinkState State {
get {
return state;
}
set {
state = value;
}
}
///
/// The name for the link - useful for indexing by key.
///
[
DefaultValue(""),
SRCategory(SR.CatAppearance),
SRDescription(SR.TreeNodeNodeNameDescr)
]
public string Name {
get {
return name == null ? "" : name;
}
set {
this.name = value;
}
}
///
/// [To be supplied.]
///
public int Start {
get {
return start;
}
set {
if (start != value) {
start = value;
if (owner != null) {
owner.links.Sort(LinkLabel.linkComparer);
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
}
}
///
/// [To be supplied.]
///
[DefaultValue(false)]
public bool Visited {
get {
return(State & LinkState.Visited) == LinkState.Visited;
}
set {
bool old = Visited;
if (value) {
State |= LinkState.Visited;
}
else {
State &= ~LinkState.Visited;
}
if (old != Visited && owner != null) {
owner.InvalidateLink(this);
}
}
}
internal Region VisualRegion {
get {
return visualRegion;
}
set {
visualRegion = value;
}
}
}
///
/// [To be supplied.]
///
private class LinkComparer : IComparer {
int IComparer.Compare(object link1, object link2) {
Debug.Assert(link1 != null && link2 != null, "Null objects sent for comparison");
int pos1 = ((Link)link1).Start;
int pos2 = ((Link)link2).Start;
return pos1 - pos2;
}
}
///
///
[System.Runtime.InteropServices.ComVisible(true)]
internal class LinkLabelAccessibleObject : LabelAccessibleObject {
///
///
public LinkLabelAccessibleObject(LinkLabel owner) : base(owner) {
}
///
///
public override AccessibleObject GetChild(int index) {
if (index >= 0 && index < ((LinkLabel)Owner).Links.Count) {
return new LinkAccessibleObject(((LinkLabel)Owner).Links[index]);
}
else {
return null;
}
}
public override System.Windows.Forms.AccessibleObject HitTest(int x, int y) {
Point p = Owner.PointToClient(new Point(x, y));
Link hit = ((LinkLabel)Owner).PointInLink(p.X, p.Y);
if (hit != null) {
return new LinkAccessibleObject(hit);
}
if (this.Bounds.Contains(x, y)) {
return this;
}
return null;
}
///
///
public override int GetChildCount() {
return((LinkLabel)Owner).Links.Count;
}
}
///
///
[System.Runtime.InteropServices.ComVisible(true)]
internal class LinkAccessibleObject : AccessibleObject {
private Link link;
public LinkAccessibleObject(Link link) : base() {
this.link = link;
}
public override Rectangle Bounds {
get {
Region region = link.VisualRegion;
Graphics g = null;
IntSecurity.ObjectFromWin32Handle.Assert();
try
{
g = Graphics.FromHwnd(link.Owner.Handle);
}
finally
{
CodeAccessPermission.RevertAssert();
}
// Make sure we have a region for this link
//
if (region == null) {
link.Owner.EnsureRun(g);
region = link.VisualRegion;
if (region == null) {
g.Dispose();
return Rectangle.Empty;
}
}
Rectangle rect;
try {
rect = Rectangle.Ceiling(region.GetBounds(g));
}
finally {
g.Dispose();
}
// Translate rect to screen coordinates
//
return link.Owner.RectangleToScreen(rect);
}
}
public override string DefaultAction {
get {
return SR.GetString(SR.AccessibleActionClick);
}
}
public override string Description {
get {
return link.Description;
}
}
public override string Name {
get {
string text = link.Owner.Text;
int charStart = LinkLabel.ConvertToCharIndex(link.Start, text);
int charEnd = LinkLabel.ConvertToCharIndex(link.Start + link.Length, text);
return text.Substring(charStart, charEnd - charStart);
}
set {
base.Name = value;
}
}
public override AccessibleObject Parent {
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
get {
return link.Owner.AccessibilityObject;
}
}
public override AccessibleRole Role {
get {
return AccessibleRole.Link;
}
}
public override AccessibleStates State {
get {
AccessibleStates state = AccessibleStates.Focusable;
// Selected state
//
if (link.Owner.FocusLink == link) {
state |= AccessibleStates.Focused;
}
return state;
}
}
public override string Value {
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
get {
return Name;
}
}
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
public override void DoDefaultAction() {
link.Owner.OnLinkClicked(new LinkLabelLinkClickedEventArgs(link));
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Windows.Forms {
using Microsoft.Win32;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Drawing.Design;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Runtime.Remoting;
using System.Runtime.Serialization.Formatters;
using System.Security;
using System.Security.Permissions;
using System.Text;
using System.Windows.Forms.ComponentModel;
using System.Globalization;
using System.Windows.Forms;
using System.Windows.Forms.Layout;
using System.Windows.Forms.Internal;
using System;
///
///
/// Displays text that can contain a hyperlink.
///
///
[
ComVisible(true),
ClassInterface(ClassInterfaceType.AutoDispatch),
DefaultEvent("LinkClicked"),
ToolboxItem("System.Windows.Forms.Design.AutoSizeToolboxItem," + AssemblyRef.SystemDesign),
SRDescription(SR.DescriptionLinkLabel)
]
public class LinkLabel : Label, IButtonControl {
static readonly object EventLinkClicked = new object();
static Color iedisabledLinkColor = Color.Empty;
static LinkComparer linkComparer = new LinkComparer();
///
/// The dialog result that will be sent to the parent dialog form when
/// we are clicked.
///
DialogResult dialogResult;
Color linkColor = Color.Empty;
Color activeLinkColor = Color.Empty;
Color visitedLinkColor = Color.Empty;
Color disabledLinkColor = Color.Empty;
Font linkFont;
Font hoverLinkFont;
bool textLayoutValid = false;
bool receivedDoubleClick = false;
ArrayList links = new ArrayList(2);
Link focusLink = null;
LinkCollection linkCollection = null;
Region textRegion = null;
Cursor overrideCursor = null;
bool processingOnGotFocus; // used to avoid raising the OnGotFocus event twice after selecting a focus link.
LinkBehavior linkBehavior = System.Windows.Forms.LinkBehavior.SystemDefault;
///
///
/// Initializes a new default instance of the
///
public LinkLabel() : base() {
SetStyle(ControlStyles.AllPaintingInWmPaint
| ControlStyles.OptimizedDoubleBuffer
| ControlStyles.Opaque
| ControlStyles.UserPaint
| ControlStyles.StandardClick
| ControlStyles.ResizeRedraw, true);
ResetLinkArea();
}
///
///
/// Gets or sets the color used to display active links.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelActiveLinkColorDescr)
]
public Color ActiveLinkColor {
get {
if (activeLinkColor.IsEmpty) {
return IEActiveLinkColor;
}
else {
return activeLinkColor;
}
}
set {
if (activeLinkColor != value) {
activeLinkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Gets or sets the color used to display disabled links.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelDisabledLinkColorDescr)
]
public Color DisabledLinkColor {
get {
if (disabledLinkColor.IsEmpty) {
return IEDisabledLinkColor;
}
else {
return disabledLinkColor;
}
}
set {
if (disabledLinkColor != value) {
disabledLinkColor = value;
InvalidateLink(null);
}
}
}
private Link FocusLink {
get {
return focusLink;
}
set {
if (focusLink != value) {
if (focusLink != null) {
InvalidateLink(focusLink);
}
focusLink = value;
if (focusLink != null) {
InvalidateLink(focusLink);
UpdateAccessibilityLink(focusLink);
}
}
}
}
private Color IELinkColor {
get {
return LinkUtilities.IELinkColor;
}
}
private Color IEActiveLinkColor {
get {
return LinkUtilities.IEActiveLinkColor;
}
}
private Color IEVisitedLinkColor {
get {
return LinkUtilities.IEVisitedLinkColor;
}
}
private Color IEDisabledLinkColor {
get {
if (iedisabledLinkColor.IsEmpty) {
iedisabledLinkColor = ControlPaint.Dark(DisabledColor);
}
return iedisabledLinkColor;
}
}
private Rectangle ClientRectWithPadding {
get {
return LayoutUtils.DeflateRect(ClientRectangle, Padding);
}
}
///
///
/// Gets or sets the range in the text that is treated as a link.
///
///
[
Editor("System.Windows.Forms.Design.LinkAreaEditor, " + AssemblyRef.SystemDesign, typeof(UITypeEditor)),
RefreshProperties(RefreshProperties.Repaint),
Localizable(true),
SRCategory(SR.CatBehavior),
SRDescription(SR.LinkLabelLinkAreaDescr)
]
public LinkArea LinkArea {
get {
if (links.Count == 0) {
return new LinkArea(0, 0);
}
return new LinkArea(((Link)links[0]).Start, ((Link)links[0]).Length);
}
set {
LinkArea pt = LinkArea;
links.Clear();
if (!value.IsEmpty) {
if (value.Start < 0) {
throw new ArgumentOutOfRangeException("LinkArea", value, SR.GetString(SR.LinkLabelAreaStart));
}
if (value.Length < -1) {
throw new ArgumentOutOfRangeException("LinkArea", value, SR.GetString(SR.LinkLabelAreaLength));
}
if (value.Start != 0 || value.Length != 0) {
Links.Add(new Link(this));
// Update the link area of the first link
//
((Link)links[0]).Start = value.Start;
((Link)links[0]).Length = value.Length;
}
}
UpdateSelectability();
if (!pt.Equals(LinkArea)) {
InvalidateTextLayout();
LayoutTransaction.DoLayout(ParentInternal, this, PropertyNames.LinkArea);
base.AdjustSize();
Invalidate();
}
}
}
///
///
/// Gets ir sets a value that represents how the link will be underlined.
///
///
[
DefaultValue(LinkBehavior.SystemDefault),
SRCategory(SR.CatBehavior),
SRDescription(SR.LinkLabelLinkBehaviorDescr)
]
public LinkBehavior LinkBehavior {
get {
return linkBehavior;
}
set {
//valid values are 0x0 to 0x3
if (!ClientUtils.IsEnumValid(value, (int)value, (int)LinkBehavior.SystemDefault, (int)LinkBehavior.NeverUnderline)){
throw new InvalidEnumArgumentException("LinkBehavior", (int)value, typeof(LinkBehavior));
}
if (value != linkBehavior) {
linkBehavior = value;
InvalidateLinkFonts();
InvalidateLink(null);
}
}
}
///
///
/// Gets or sets the color used to display links in normal cases.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelLinkColorDescr)
]
public Color LinkColor {
get {
if (linkColor.IsEmpty) {
return IELinkColor;
}
else {
return linkColor;
}
}
set {
if (linkColor != value) {
linkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Gets the collection of links used in a
///
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public LinkCollection Links {
get {
if (linkCollection == null) {
linkCollection = new LinkCollection(this);
}
return linkCollection;
}
}
///
///
/// Gets or sets a value indicating whether the link should be displayed as if it was visited.
///
///
[
DefaultValue(false),
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelLinkVisitedDescr)
]
public bool LinkVisited {
get {
if (links.Count == 0) {
return false;
}
else {
return((Link)links[0]).Visited;
}
}
set {
if (value != LinkVisited) {
if (links.Count == 0) {
Links.Add(new Link(this));
}
((Link)links[0]).Visited = value;
}
}
}
// link labels must always ownerdraw
//
internal override bool OwnerDraw {
get {
return true;
}
}
///
/// [To be supplied.]
///
protected Cursor OverrideCursor {
get {
return overrideCursor;
}
set {
if (overrideCursor != value) {
overrideCursor = value;
if (IsHandleCreated) {
// We want to instantly change the cursor if the mouse is within our bounds.
// This includes the case where the mouse is over one of our children
NativeMethods.POINT p = new NativeMethods.POINT();
NativeMethods.RECT r = new NativeMethods.RECT();
UnsafeNativeMethods.GetCursorPos(p);
UnsafeNativeMethods.GetWindowRect(new HandleRef(this, Handle), ref r);
//
if ((r.left <= p.x && p.x < r.right && r.top <= p.y && p.y < r.bottom) || UnsafeNativeMethods.GetCapture() == Handle)
SendMessage(NativeMethods.WM_SETCURSOR, Handle, NativeMethods.HTCLIENT);
}
}
}
}
///
///
/// Gets or sets the color used to display the link once it has been visited.
///
///
[
SRCategory(SR.CatAppearance),
SRDescription(SR.LinkLabelVisitedLinkColorDescr)
]
public Color VisitedLinkColor {
get {
if (visitedLinkColor.IsEmpty) {
return IEVisitedLinkColor;
}
else {
return visitedLinkColor;
}
}
set {
if (visitedLinkColor != value) {
visitedLinkColor = value;
InvalidateLink(null);
}
}
}
///
///
/// Occurs when the link is clicked.
///
///
[WinCategory("Action"), SRDescription(SR.LinkLabelLinkClickedDescr)]
public event LinkLabelLinkClickedEventHandler LinkClicked {
add {
Events.AddHandler(EventLinkClicked, value);
}
remove {
Events.RemoveHandler(EventLinkClicked, value);
}
}
internal static Rectangle CalcTextRenderBounds(Rectangle textRect, Rectangle clientRect, ContentAlignment align) {
int xLoc, yLoc, width, height;
if ((align & WindowsFormsUtils.AnyRightAlign) != 0) {
xLoc = clientRect.Right - textRect.Width;
} else if ((align & WindowsFormsUtils.AnyCenterAlign) != 0) {
xLoc = (clientRect.Width - textRect.Width) / 2;
} else {
xLoc = clientRect.X;
}
if ((align & WindowsFormsUtils.AnyBottomAlign) != 0) {
yLoc = clientRect.Bottom - textRect.Height;
} else if ((align & WindowsFormsUtils.AnyMiddleAlign) != 0) {
yLoc = (clientRect.Height - textRect.Height) / 2;
} else {
yLoc = clientRect.Y;
}
// If the text rect does not fit in the client rect, make it fit.
if (textRect.Width > clientRect.Width) {
xLoc = clientRect.X;
width = clientRect.Width;
} else {
width = textRect.Width;
}
if (textRect.Height > clientRect.Height) {
yLoc = clientRect.Y;
height = clientRect.Height;
} else {
height = textRect.Height;
}
return new Rectangle(xLoc, yLoc, width, height);
}
///
/// Constructs the new instance of the accessibility object for this control. Subclasses
/// should not call base.CreateAccessibilityObject.
///
protected override AccessibleObject CreateAccessibilityInstance() {
return new LinkLabelAccessibleObject(this);
}
///
///
/// Creates a handle for this control. This method is called by the .NET Framework,
/// this should not be called. Inheriting classes should always call
/// base.createHandle when overriding this method.
///
///
protected override void CreateHandle() {
base.CreateHandle();
InvalidateTextLayout();
}
///
/// Determines whether the current state of the control allows for rendering text using
/// TextRenderer (GDI).
/// The Gdi library doesn't currently have a way to calculate character ranges so we cannot
/// use it for painting link(s) within the text, but if the link are is null or covers the
/// entire text we are ok since it is just one area with the same size of the text binding
/// area.
///
internal override bool CanUseTextRenderer {
get{
// If no link or the LinkArea is one and covers the entire text, we can support UseCompatibleTextRendering = false.
// Observe that LinkArea refers to the first link always.
StringInfo stringInfo = new StringInfo( this.Text );
return this.LinkArea.Start == 0 && ( this.LinkArea.Length == 0 || this.LinkArea.Length == stringInfo.LengthInTextElements );
}
}
internal override bool UseGDIMeasuring() {
return !UseCompatibleTextRendering;
}
///
/// Converts the character index into char index of the string
/// This method is copied in LinkCollectionEditor.cs. Update the other
/// one as well if you change this method.
/// This method mainly deal with surrogate. Suppose we
/// have a string consisting of 3 surrogates, and we want the
/// second character, then the index we need should be 2 instead of
/// 1, and this method returns the correct index.
///
private static int ConvertToCharIndex(int index, string text) {
if (index <= 0) {
return 0;
}
if (String.IsNullOrEmpty(text)) {
Debug.Assert(text != null, "string should not be null");
//do no conversion, just return the original value passed in
return index;
}
//VSWhidbey 217272: Dealing with surrogate characters
//in some languages, characters can expand over multiple
//chars, using StringInfo lets us properly deal with it.
StringInfo stringInfo = new StringInfo(text);
int numTextElements = stringInfo.LengthInTextElements;
//index is greater than the length of the string
if (index > numTextElements) {
return index - numTextElements + text.Length; //pretend all the characters after are ASCII characters
}
//return the length of the substring which has specified number of characters
string sub = stringInfo.SubstringByTextElements(0, index);
return sub.Length;
}
///
/// Ensures that we have analyzed the text run so that we can render each segment
/// and link.
///
private void EnsureRun(Graphics g) {
// bail early if everything is valid!
//
if (textLayoutValid) {
return;
}
if (this.textRegion != null) {
this.textRegion.Dispose();
this.textRegion = null;
}
// bail early for no text
//
if (Text.Length == 0) {
Links.Clear();
Links.Add (new Link (0, -1)); // default 'magic' link.
textLayoutValid = true;
return;
}
StringFormat textFormat = CreateStringFormat();
string text = Text;
try {
Font alwaysUnderlined = new Font(Font, Font.Style | FontStyle.Underline);
Graphics created = null;
try {
if (g == null) {
g = created = CreateGraphicsInternal();
}
if( UseCompatibleTextRendering ){
Region[] textRegions = g.MeasureCharacterRanges (text, alwaysUnderlined, ClientRectWithPadding, textFormat);
int regionIndex = 0;
for (int i=0; i
/// Calculate character ranges taking into account the locale. Provided for surrogate chars support.
///
private CharacterRange[] AdjustCharacterRangesForSurrogateChars(){
string text = Text;
if (String.IsNullOrEmpty(text)) {
return new CharacterRange[]{};
}
StringInfo stringInfo = new StringInfo(text);
int textLen = stringInfo.LengthInTextElements;
ArrayList ranges = new ArrayList(Links.Count);
foreach (Link link in Links) {
int charStart = ConvertToCharIndex(link.Start, text);
int charEnd = ConvertToCharIndex(link.Start + link.Length, text);
if (LinkInText(charStart, charEnd - charStart)) {
int length = (int) Math.Min(link.Length, textLen - link.Start);
ranges.Add(new CharacterRange(charStart, ConvertToCharIndex(link.Start + length, text) - charStart));
}
}
CharacterRange[] regions = new CharacterRange[ranges.Count + 1];
ranges.CopyTo(regions, 0);
regions[regions.Length - 1] = new CharacterRange(0, text.Length);
return regions;
}
///
/// Determines whether the whole link label contains only one link,
/// and the link runs from the beginning of the label to the end of it
///
private bool IsOneLink() {
if (links == null || links.Count != 1 || Text == null) {
return false;
}
StringInfo stringInfo = new StringInfo(Text);
if (LinkArea.Start == 0 && LinkArea.Length == stringInfo.LengthInTextElements) {
return true;
}
return false;
}
///
/// Determines if the given client coordinates is contained within a portion
/// of a link area.
///
protected Link PointInLink(int x, int y) {
Graphics g = CreateGraphicsInternal();
Link hit = null;
try {
EnsureRun(g);
foreach (Link link in links) {
if (link.VisualRegion != null && link.VisualRegion.IsVisible(x, y, g)) {
hit = link;
break;
}
}
}
finally {
g.Dispose();
g = null;
}
return hit;
}
///
/// Invalidates only the portions of the text that is linked to
/// the specified link. If link is null, then all linked text
/// is invalidated.
///
private void InvalidateLink(Link link) {
if (IsHandleCreated) {
if (link == null || link.VisualRegion == null || IsOneLink()) {
Invalidate();
}
else{
Invalidate(link.VisualRegion);
}
}
}
///
/// Invalidates the current set of fonts we use when painting
/// links. The fonts will be recreated when needed.
///
private void InvalidateLinkFonts() {
if (linkFont != null) {
linkFont.Dispose();
}
if (hoverLinkFont != null && hoverLinkFont != linkFont) {
hoverLinkFont.Dispose();
}
linkFont = null;
hoverLinkFont = null;
}
private void InvalidateTextLayout() {
textLayoutValid = false;
}
private bool LinkInText(int start, int length) {
return(0 <= start && start < Text.Length && 0 < length);
}
///
///
/// Gets or sets a value that is returned to the
/// parent form when the link label.
/// is clicked.
///
///
DialogResult IButtonControl.DialogResult {
get {
return dialogResult;
}
set {
//valid values are 0x0 to 0x7
if (!ClientUtils.IsEnumValid(value, (int)value, (int)DialogResult.None, (int)DialogResult.No))
{
throw new InvalidEnumArgumentException("value", (int)value, typeof(DialogResult));
}
dialogResult = value;
}
}
///
///
/// Raises the
///
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Security", "CA2106:SecureAsserts")]
protected override void OnGotFocus(EventArgs e) {
if (!this.processingOnGotFocus) {
base.OnGotFocus(e);
this.processingOnGotFocus = true;
}
try {
Link focusLink = FocusLink;
if (focusLink == null) {
// SECREVIEW: This assert is required because the call to Select will generate a call to SetActiveControl which have a demand,
// it is safe since no input from user code is processed while setting the active control originated this way.
//
IntSecurity.ModifyFocus.Assert();
// Set focus on first link.
// This will raise the OnGotFocus event again but it will not be processed because processingOnGotFocus is true.
Select(true /*directed*/, true /*forward*/);
}
else {
InvalidateLink(focusLink);
UpdateAccessibilityLink(focusLink);
}
}
finally {
if (this.processingOnGotFocus) {
this.processingOnGotFocus = false;
}
}
}
///
///
/// Raises the
///
protected override void OnLostFocus(EventArgs e) {
base.OnLostFocus(e);
if (FocusLink != null) {
InvalidateLink(FocusLink);
}
}
///
///
/// Raises the
///
protected override void OnKeyDown(KeyEventArgs e) {
base.OnKeyDown(e);
if (e.KeyCode == Keys.Enter) {
if (FocusLink != null && FocusLink.Enabled) {
OnLinkClicked(new LinkLabelLinkClickedEventArgs(FocusLink));
}
}
}
///
///
/// Raises the
///
protected override void OnMouseLeave(EventArgs e) {
base.OnMouseLeave(e);
if (!Enabled) {
return;
}
foreach (Link link in links) {
if ((link.State & LinkState.Hover) == LinkState.Hover
|| (link.State & LinkState.Active) == LinkState.Active) {
bool activeChanged = (link.State & LinkState.Active) == LinkState.Active;
link.State &= ~(LinkState.Hover | LinkState.Active);
if (activeChanged || hoverLinkFont != linkFont) {
InvalidateLink(link);
}
OverrideCursor = null;
}
}
}
///
///
/// Raises the
///
protected override void OnMouseDown(MouseEventArgs e) {
base.OnMouseDown(e);
if (!Enabled || e.Clicks > 1) {
receivedDoubleClick = true;
return;
}
for (int i=0; i
///
/// Raises the
///
protected override void OnMouseUp(MouseEventArgs e) {
base.OnMouseUp(e);
// bug 95211 : don't do any Handle-related operations when in disposing state
if (Disposing || IsDisposed) {
return;
}
if (!Enabled || e.Clicks > 1 || receivedDoubleClick) {
receivedDoubleClick = false;
return;
}
for (int i=0; i
///
/// Raises the
///
protected override void OnMouseMove(MouseEventArgs e) {
base.OnMouseMove(e);
if (!Enabled) {
return;
}
Link hoverLink = null;
foreach (Link link in links) {
if ((link.State & LinkState.Hover) == LinkState.Hover) {
hoverLink = link;
break;
}
}
Link pointIn = PointInLink(e.X, e.Y);
if (pointIn != hoverLink) {
if (hoverLink != null) {
hoverLink.State &= ~LinkState.Hover;
}
if (pointIn != null) {
pointIn.State |= LinkState.Hover;
if (pointIn.Enabled) {
OverrideCursor = Cursors.Hand;
}
}
else {
OverrideCursor = null;
}
if (hoverLinkFont != linkFont) {
if (hoverLink != null) {
InvalidateLink(hoverLink);
}
if (pointIn != null) {
InvalidateLink(pointIn);
}
}
}
}
///
///
/// Raises the
///
protected virtual void OnLinkClicked(LinkLabelLinkClickedEventArgs e) {
LinkLabelLinkClickedEventHandler handler = (LinkLabelLinkClickedEventHandler)Events[EventLinkClicked];
if (handler != null) {
handler(this, e);
}
}
protected override void OnPaddingChanged(EventArgs e) {
base.OnPaddingChanged(e);
InvalidateTextLayout();
}
///
///
/// Raises the
///
protected override void OnPaint(PaintEventArgs e) {
RectangleF finalrect = RectangleF.Empty; //the focus rectangle if there is only one link
Animate();
ImageAnimator.UpdateFrames();
EnsureRun(e.Graphics);
// bail early for no text
//
if (Text.Length == 0) {
PaintLinkBackground(e.Graphics);
}
// Paint enabled link label
//
else {
if (AutoEllipsis) {
Rectangle clientRect = this.ClientRectWithPadding;
Size preferredSize = GetPreferredSize(new Size(clientRect.Width, clientRect.Height));
showToolTip = (clientRect.Width < preferredSize.Width || clientRect.Height < preferredSize.Height);
}
else {
showToolTip = false;
}
if (this.Enabled) { // Control.Enabled not to be confused with Link.Enabled
bool optimizeBackgroundRendering = !GetStyle(ControlStyles.OptimizedDoubleBuffer);
SolidBrush foreBrush = new SolidBrush(ForeColor);
SolidBrush linkBrush = new SolidBrush(LinkColor);
try {
if (!optimizeBackgroundRendering) {
PaintLinkBackground(e.Graphics);
}
LinkUtilities.EnsureLinkFonts(this.Font, this.LinkBehavior, ref this.linkFont, ref this.hoverLinkFont);
Region originalClip = e.Graphics.Clip;
try {
if (IsOneLink()) {
//exclude the area to draw the focus rectangle
e.Graphics.Clip = originalClip;
RectangleF[] rects = ((Link)links[0]).VisualRegion.GetRegionScans(e.Graphics.Transform);
if (rects != null && rects.Length > 0) {
if (UseCompatibleTextRendering) {
finalrect = new RectangleF(rects[0].Location, SizeF.Empty);
foreach (RectangleF rect in rects) {
finalrect = RectangleF.Union(finalrect, rect);
}
}
else {
finalrect = this.ClientRectWithPadding;
Size finalRectSize = finalrect.Size.ToSize();
Size requiredSize = MeasureTextCache.GetTextSize(Text, Font, finalRectSize, CreateTextFormatFlags(finalRectSize));
finalrect.Width = requiredSize.Width;
if (requiredSize.Height < finalrect.Height) {
finalrect.Height = requiredSize.Height;
}
finalrect = CalcTextRenderBounds(System.Drawing.Rectangle.Round(finalrect) /*textRect*/, this.ClientRectWithPadding /*clientRect*/, RtlTranslateContent(this.TextAlign));
}
e.Graphics.ExcludeClip(new Region(finalrect));
}
}
else {
foreach (Link link in links) {
if (link.VisualRegion != null) {
e.Graphics.ExcludeClip(link.VisualRegion);
}
}
}
PaintLink(e.Graphics, null, foreBrush, linkBrush, optimizeBackgroundRendering, finalrect);
foreach (Link link in links) {
PaintLink(e.Graphics, link, foreBrush, linkBrush, optimizeBackgroundRendering, finalrect);
}
if (optimizeBackgroundRendering) {
e.Graphics.Clip = originalClip;
e.Graphics.ExcludeClip(this.textRegion);
PaintLinkBackground(e.Graphics);
}
}
finally {
e.Graphics.Clip = originalClip;
}
}
finally {
foreBrush.Dispose();
linkBrush.Dispose();
}
}
// Paint disabled link label (disabled control, not to be confused with disabled link).
//
else {
Region originalClip = e.Graphics.Clip;
try {
// We need to paint the background first before clipping to textRegion because it is calculated using
// ClientRectWithPadding which in some cases is smaller that ClientRectangle.
//
PaintLinkBackground(e.Graphics);
e.Graphics.IntersectClip(this.textRegion);
Color foreColor;
if (UseCompatibleTextRendering) {
// APPCOMPAT: Use DisabledColor because Everett used DisabledColor.
// (ie, dont use Graphics.GetNearestColor(DisabledColor.)
// vsw 495322.
StringFormat stringFormat = CreateStringFormat();
ControlPaint.DrawStringDisabled(e.Graphics, Text, Font, DisabledColor, ClientRectWithPadding, stringFormat);
}
else {
IntPtr hdc = e.Graphics.GetHdc();
try {
using (WindowsGraphics wg = WindowsGraphics.FromHdc(hdc)) {
foreColor = wg.GetNearestColor(DisabledColor);
}
}
finally {
e.Graphics.ReleaseHdc();
}
Rectangle clientRectWidthPadding = ClientRectWithPadding;
ControlPaint.DrawStringDisabled(e.Graphics, Text, Font, foreColor, clientRectWidthPadding, CreateTextFormatFlags(clientRectWidthPadding.Size));
}
}
finally {
e.Graphics.Clip = originalClip;
}
}
}
// We can't call base.OnPaint because labels paint differently from link labels,
// but we still need to raise the Paint event.
//
RaisePaintEvent(this, e);
}
///
/// [To be supplied.]
///
protected override void OnPaintBackground(PaintEventArgs e) {
Image i = this.Image;
if (i != null) {
Region oldClip = e.Graphics.Clip;
Rectangle imageBounds = CalcImageRenderBounds(i, ClientRectangle, RtlTranslateAlignment(ImageAlign));
e.Graphics.ExcludeClip(imageBounds);
try {
base.OnPaintBackground(e);
}
finally {
e.Graphics.Clip = oldClip;
}
e.Graphics.IntersectClip(imageBounds);
try {
base.OnPaintBackground(e);
DrawImage(e.Graphics, i, ClientRectangle, RtlTranslateAlignment(ImageAlign));
}
finally {
e.Graphics.Clip = oldClip;
}
}
else {
base.OnPaintBackground(e);
}
}
///
/// [To be supplied.]
///
protected override void OnFontChanged(EventArgs e) {
base.OnFontChanged(e);
InvalidateTextLayout();
InvalidateLinkFonts();
Invalidate();
}
///
///
protected override void OnAutoSizeChanged(EventArgs e) {
base.OnAutoSizeChanged(e);
InvalidateTextLayout();
}
///
/// Overriden by LinkLabel.
///
internal override void OnAutoEllipsisChanged(/*EventArgs e*/) {
base.OnAutoEllipsisChanged(/*e*/);
InvalidateTextLayout();
}
///
/// [To be supplied.]
///
protected override void OnEnabledChanged(EventArgs e) {
base.OnEnabledChanged(e);
if (!Enabled) {
for (int i=0; i
/// [To be supplied.]
///
protected override void OnTextChanged(EventArgs e) {
base.OnTextChanged(e);
InvalidateTextLayout();
UpdateSelectability();
}
///
/// [To be supplied.]
///
protected override void OnTextAlignChanged(EventArgs e) {
base.OnTextAlignChanged(e);
InvalidateTextLayout();
UpdateSelectability();
}
private void PaintLink(Graphics g, Link link, SolidBrush foreBrush, SolidBrush linkBrush, bool optimizeBackgroundRendering, RectangleF finalrect) {
// link = null means paint the whole text
Debug.Assert(g != null, "Must pass valid graphics");
Debug.Assert(foreBrush != null, "Must pass valid foreBrush");
Debug.Assert(linkBrush != null, "Must pass valid linkBrush");
Font font = Font;
if (link != null) {
if (link.VisualRegion != null) {
Color brushColor = Color.Empty;
LinkState linkState = link.State;
if ((linkState & LinkState.Hover) == LinkState.Hover) {
font = hoverLinkFont;
}
else {
font = linkFont;
}
if (link.Enabled) { // Not to be confused with Control.Enabled.
if ((linkState & LinkState.Active) == LinkState.Active) {
brushColor = ActiveLinkColor;
}
else if ((linkState & LinkState.Visited) == LinkState.Visited) {
brushColor = VisitedLinkColor;
}
// else use linkBrush
}
else {
brushColor = DisabledLinkColor;
}
if (IsOneLink()) {
g.Clip = new Region(finalrect);
}
else {
g.Clip = link.VisualRegion;
}
if (optimizeBackgroundRendering) {
PaintLinkBackground(g);
}
if( UseCompatibleTextRendering ){
SolidBrush useBrush = brushColor == Color.Empty ? linkBrush : new SolidBrush( brushColor );
StringFormat stringFormat = CreateStringFormat();
g.DrawString(Text, font, useBrush, ClientRectWithPadding, stringFormat);
if( useBrush != linkBrush ){
useBrush.Dispose();
}
}
else{
if(brushColor == Color.Empty ){
brushColor = linkBrush.Color;
}
IntPtr hdc = g.GetHdc();
try{
using( WindowsGraphics wg = WindowsGraphics.FromHdc( hdc ) ) {
brushColor = wg.GetNearestColor(brushColor);
}
}
finally{
g.ReleaseHdc();
}
Rectangle clientRectWithPadding = ClientRectWithPadding;
TextRenderer.DrawText(g, Text, font, clientRectWithPadding, brushColor, CreateTextFormatFlags(clientRectWithPadding.Size));
}
if (Focused && ShowFocusCues && FocusLink == link) {
// Get the rectangles making up the visual region, and draw
// each one.
RectangleF[] rects = link.VisualRegion.GetRegionScans(g.Transform);
if( rects != null && rects.Length > 0 ){
Rectangle focusRect;
if (IsOneLink()) {
//draw one merged focus rectangle
focusRect = Rectangle.Ceiling(finalrect);
Debug.Assert(finalrect != RectangleF.Empty, "finalrect should be initialized");
ControlPaint.DrawFocusRectangle(g, focusRect, ForeColor, BackColor);
}
else {
foreach (RectangleF rect in rects) {
ControlPaint.DrawFocusRectangle(g, Rectangle.Ceiling(rect), ForeColor, BackColor);
}
}
}
}
}
// no else clause... we don't paint anything if we are given a link with no visual region.
//
}
else { // Painting with no link.
g.IntersectClip(this.textRegion);
if (optimizeBackgroundRendering) {
PaintLinkBackground(g);
}
if( UseCompatibleTextRendering ){
StringFormat stringFormat = CreateStringFormat();
g.DrawString(Text, font, foreBrush, ClientRectWithPadding, stringFormat);
}
else{
Color color;
IntPtr hdc = g.GetHdc();
try{
using( WindowsGraphics wg = WindowsGraphics.FromHdc( hdc ) ) {
color = wg.GetNearestColor(foreBrush.Color);
}
}
finally{
g.ReleaseHdc();
}
Rectangle clientRectWithPadding = ClientRectWithPadding;
TextRenderer.DrawText(g, Text, font, clientRectWithPadding, color, CreateTextFormatFlags(clientRectWithPadding.Size));
}
}
}
private void PaintLinkBackground(Graphics g) {
using (PaintEventArgs e = new PaintEventArgs(g, ClientRectangle)) {
InvokePaintBackground(this, e);
}
}
///
///
/// Processes a dialog key. This method is called during message pre-processing
/// to handle dialog characters, such as TAB, RETURN, ESCAPE, and arrow keys. This
/// method is called only if the isInputKey() method indicates that the control
/// isn't interested in the key. processDialogKey() simply sends the character to
/// the parent's processDialogKey() method, or returns false if the control has no
/// parent. The Form class overrides this method to perform actual processing
/// of dialog keys. When overriding processDialogKey(), a control should return true
/// to indicate that it has processed the key. For keys that aren't processed by the
/// control, the result of "base.processDialogChar()" should be returned. Controls
/// will seldom, if ever, need to override this method.
///
///
[UIPermission(SecurityAction.LinkDemand, Window=UIPermissionWindow.AllWindows)]
protected override bool ProcessDialogKey(Keys keyData) {
if ((keyData & (Keys.Alt | Keys.Control)) != Keys.Alt) {
Keys keyCode = keyData & Keys.KeyCode;
switch (keyCode) {
case Keys.Tab:
if (TabStop) {
bool forward = (keyData & Keys.Shift) != Keys.Shift;
if (FocusNextLink(forward)) {
return true;
}
}
break;
case Keys.Up:
case Keys.Left:
if (FocusNextLink(false)) {
return true;
}
break;
case Keys.Down:
case Keys.Right:
if (FocusNextLink(true)) {
return true;
}
break;
}
}
return base.ProcessDialogKey(keyData);
}
private bool FocusNextLink(bool forward) {
int focusIndex = -1;
if (focusLink != null) {
for (int i=0; i= 0) {
test = Links[focusIndex];
charStart = ConvertToCharIndex(test.Start, text);
charEnd = ConvertToCharIndex(test.Start + test.Length, text);
}
else {
test = null;
}
} while (test != null
&& !test.Enabled
&& LinkInText(charStart, charEnd - charStart));
}
if (focusIndex < 0 || focusIndex >= links.Count) {
return -1;
}
else {
return focusIndex;
}
}
private void ResetLinkArea() {
LinkArea = new LinkArea(0, -1);
}
internal void ResetActiveLinkColor() {
activeLinkColor = Color.Empty;
}
internal void ResetDisabledLinkColor() {
disabledLinkColor = Color.Empty;
}
internal void ResetLinkColor() {
linkColor = Color.Empty;
InvalidateLink(null);
}
private void ResetVisitedLinkColor() {
visitedLinkColor = Color.Empty;
}
///
///
/// Performs the work of setting the bounds of this control. Inheriting classes
/// can overide this function to add size restrictions. Inheriting classes must call
/// base.setBoundsCore to actually cause the bounds of the control to change.
///
///
protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified) {
// we cache too much state to try and optimize this (regions, etc)... it is best
// to always relayout here... If we want to resurect this code in the future,
// remember that we need to handle a word wrapped top aligned text that
// will become newly exposed (and therefore layed out) when we resize...
//
/*
ContentAlignment anyTop = ContentAlignment.TopLeft | ContentAlignment.TopCenter | ContentAlignment.TopRight;
if ((TextAlign & anyTop) == 0 || Width != width || (Image != null && (ImageAlign & anyTop) == 0)) {
InvalidateTextLayout();
Invalidate();
}
*/
InvalidateTextLayout();
Invalidate();
base.SetBoundsCore(x, y, width, height, specified);
}
///
/// [To be supplied.]
///
protected override void Select(bool directed, bool forward) {
if (directed) {
// In a multi-link label, if the tab came from another control, we want to keep the currently
// focused link, otherwise, we set the focus to the next link.
if (links.Count > 0) {
// Find which link is currently focused
//
int focusIndex = -1;
if (FocusLink != null) {
focusIndex = links.IndexOf(FocusLink);
}
// We could be getting focus from ourself, so we must
// invalidate each time.
//
FocusLink = null;
int newFocus = GetNextLinkIndex(focusIndex, forward);
if (newFocus == -1) {
if (forward) {
newFocus = GetNextLinkIndex(-1, forward); // -1, so "next" will be 0
}
else {
newFocus = GetNextLinkIndex(links.Count, forward); // Count, so "next" will be Count-1
}
}
if (newFocus != -1) {
FocusLink = (Link)links[newFocus];
}
}
}
base.Select(directed, forward);
}
///
///
/// Determines if the color for active links should remain the same.
///
///
internal bool ShouldSerializeActiveLinkColor() {
return !activeLinkColor.IsEmpty;
}
///
///
/// Determines if the color for disabled links should remain the same.
///
///
internal bool ShouldSerializeDisabledLinkColor() {
return !disabledLinkColor.IsEmpty;
}
///
///
/// Determines if the range in text that is treated as a
/// link should remain the same.
///
///
private bool ShouldSerializeLinkArea() {
if (links.Count == 1) {
// use field access to find out if "length" is really -1
return Links[0].Start != 0 || Links[0].length != -1;
}
return true;
}
///
///
/// Determines if the color of links in normal cases should remain the same.
///
///
internal bool ShouldSerializeLinkColor() {
return !linkColor.IsEmpty;
}
///
/// Determines whether designer should generate code for setting the UseCompatibleTextRendering or not.
/// DefaultValue(false)
///
private bool ShouldSerializeUseCompatibleTextRendering() {
// Serialize code if LinkLabel cannot support the feature or the property's value is not the default.
return !CanUseTextRenderer || UseCompatibleTextRendering != Control.UseCompatibleTextRenderingDefault;
}
///
///
/// Determines if the color of links that have been visited should remain the same.
///
///
private bool ShouldSerializeVisitedLinkColor() {
return !visitedLinkColor.IsEmpty;
}
///
///
/// Update accessibility with the currently focused link.
///
///
private void UpdateAccessibilityLink(Link focusLink) {
if (!IsHandleCreated) {
return;
}
int focusIndex = -1;
for (int i=0; i
/// Validates that no links overlap. This will throw an exception if
/// they do.
///
private void ValidateNoOverlappingLinks() {
for (int x=0; x
/// Updates the label's ability to get focus. If there are
/// any links in the label, then the label can get focus,
/// else it can't.
///
private void UpdateSelectability() {
LinkArea pt = LinkArea;
bool selectable = false;
string text = Text;
int charStart = ConvertToCharIndex(pt.Start, text);
int charEnd = ConvertToCharIndex(pt.Start + pt.Length, text);
if (LinkInText(charStart, charEnd - charStart)) {
selectable = true;
}
else {
// If a link is currently focused, de-select it
//
if (FocusLink != null) {
FocusLink = null;
}
}
OverrideCursor = null;
TabStop = selectable;
SetStyle(ControlStyles.Selectable, selectable);
}
///
/// Determines whether to use compatible text rendering engine (GDI+) or not (GDI).
///
[
// DefaultValue(false), - // See ShouldSerailizeUseCompatibleTextRendering method.
RefreshProperties(RefreshProperties.Repaint),
SRCategory(SR.CatBehavior),
SRDescription(SR.UseCompatibleTextRenderingDescr)
]
public new bool UseCompatibleTextRendering {
get {
Debug.Assert( CanUseTextRenderer || base.UseCompatibleTextRendering, "Using GDI text rendering when CanUseTextRenderer reported false." );
return base.UseCompatibleTextRendering;
}
set {
if (base.UseCompatibleTextRendering != value) {
// Cache the value so it is restored if CanUseTextRenderer becomes true and the designer can undo changes to this as side effect.
base.UseCompatibleTextRendering = value;
InvalidateTextLayout();
}
}
}
///
/// Handles the WM_SETCURSOR message
///
///
///
[SecurityPermission(SecurityAction.LinkDemand, Flags=SecurityPermissionFlag.UnmanagedCode)]
protected override void WndProc(ref Message msg) {
switch (msg.Msg) {
case NativeMethods.WM_SETCURSOR:
WmSetCursor(ref msg);
break;
default:
base.WndProc(ref msg);
break;
}
}
///
/// [To be supplied.]
///
public class LinkCollection : IList {
private LinkLabel owner;
private bool linksAdded = false; //whether we should serialize the linkCollection
/// A caching mechanism for key accessor
/// We use an index here rather than control so that we don't have lifetime
/// issues by holding on to extra references.
/// Note this is not Thread Safe - but Winforms has to be run in a STA anyways.
private int lastAccessedIndex = -1;
///
/// [To be supplied.]
///
public LinkCollection(LinkLabel owner) {
if (owner == null)
throw new ArgumentNullException("owner");
this.owner = owner;
}
///
/// [To be supplied.]
///
public virtual Link this[int index] {
get {
return(Link)owner.links[index];
}
set {
owner.links[index] = value;
owner.links.Sort(LinkLabel.linkComparer);
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
///
/// Retrieves the child control with the specified key.
///
public virtual Link this[string key] {
get {
// We do not support null and empty string as valid keys.
if (string.IsNullOrEmpty(key)){
return null;
}
// Search for the key in our collection
int index = IndexOfKey(key);
if (IsValidIndex(index)) {
return this[index];
}
else {
return null;
}
}
}
///
/// [To be supplied.]
///
[Browsable(false)]
public int Count {
get {
return owner.links.Count;
}
}
///
/// whether we have added a non-trivial link to the collection
///
public bool LinksAdded {
get {
return linksAdded;
}
}
///
/// [To be supplied.]
///
public bool IsReadOnly {
get {
return false;
}
}
///
/// [To be supplied.]
///
public Link Add(int start, int length) {
if (length != 0) {
linksAdded = true;
}
return Add(start, length, null);
}
///
/// [To be supplied.]
///
public Link Add(int start, int length, object linkData) {
if (length != 0) {
linksAdded = true;
}
// check for the special case where the list is in the "magic"
// state of having only the default link in it. In that case
// we want to clear the list before adding this link.
//
if (owner.links.Count == 1
&& this[0].Start == 0
&& this[0].length == -1) {
owner.links.Clear();
}
Link l = new Link(owner);
l.Start = start;
l.Length = length;
l.LinkData = linkData;
Add(l);
return l;
}
///
/// [To be supplied.]
///
public int Add(Link value) {
if (value != null && value.Length != 0) {
linksAdded = true;
}
// check for the special case where the list is in the "magic"
// state of having only the default link in it. In that case
// we want to clear the list before adding this link.
//
if (owner.links.Count == 1
&& this[0].Start == 0
&& this[0].length == -1) {
owner.links.Clear();
}
// Set the owner control for this link
value.Owner = this.owner;
owner.links.Add(value);
if (this.owner.AutoSize) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
if (owner.Links.Count > 1) {
owner.links.Sort(LinkLabel.linkComparer);
}
owner.ValidateNoOverlappingLinks();
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
if (owner.Links.Count > 1) {
return IndexOf(value);
}
else {
return 0;
}
}
///
/// [To be supplied.]
///
public bool Contains(Link link) {
return owner.links.Contains(link);
}
///
/// Returns true if the collection contains an item with the specified key, false otherwise.
///
public virtual bool ContainsKey(string key) {
return IsValidIndex(IndexOfKey(key));
}
///
/// [To be supplied.]
///
public int IndexOf(Link link) {
return owner.links.IndexOf(link);
}
///
/// The zero-based index of the first occurrence of value within the entire CollectionBase, if found; otherwise, -1.
///
public virtual int IndexOfKey(String key) {
// Step 0 - Arg validation
if (string.IsNullOrEmpty(key)){
return -1; // we dont support empty or null keys.
}
// step 1 - check the last cached item
if (IsValidIndex(lastAccessedIndex))
{
if (WindowsFormsUtils.SafeCompareStrings(this[lastAccessedIndex].Name, key, /* ignoreCase = */ true)) {
return lastAccessedIndex;
}
}
// step 2 - search for the item
for (int i = 0; i < this.Count; i ++) {
if (WindowsFormsUtils.SafeCompareStrings(this[i].Name, key, /* ignoreCase = */ true)) {
lastAccessedIndex = i;
return i;
}
}
// step 3 - we didn't find it. Invalidate the last accessed index and return -1.
lastAccessedIndex = -1;
return -1;
}
///
/// Determines if the index is valid for the collection.
///
///
/// Remove all links from the linkLabel.
///
public virtual void Clear() {
bool doLayout = this.owner.links.Count > 0 && this.owner.AutoSize;
owner.links.Clear();
if (doLayout) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
}
///
/// [To be supplied.]
///
public IEnumerator GetEnumerator() {
if (owner.links != null) {
return owner.links.GetEnumerator();
}
else {
return new Link[0].GetEnumerator();
}
}
///
/// [To be supplied.]
///
public void Remove(Link value) {
if (value.Owner != this.owner) {
return;
}
owner.links.Remove(value);
if (this.owner.AutoSize) {
LayoutTransaction.DoLayout(this.owner.ParentInternal, this.owner, PropertyNames.Links);
this.owner.AdjustSize();
this.owner.Invalidate();
}
owner.links.Sort(LinkLabel.linkComparer);
owner.ValidateNoOverlappingLinks();
owner.UpdateSelectability();
owner.InvalidateTextLayout();
owner.Invalidate();
if (owner.FocusLink == null && owner.links.Count > 0) {
owner.FocusLink = (Link)owner.links[0];
}
}
///
/// [To be supplied.]
///
public void RemoveAt(int index) {
Remove(this[index]);
}
///
/// Removes the child control with the specified key.
///
public virtual void RemoveByKey(string key) {
int index = IndexOfKey(key);
if (IsValidIndex(index)) {
RemoveAt(index);
}
}
///
/// [To be supplied.]
///
[
TypeConverter(typeof(LinkConverter))
]
public class Link {
private int start = 0;
private object linkData = null;
private LinkState state = LinkState.Normal;
private bool enabled = true;
private Region visualRegion;
internal int length = 0;
private LinkLabel owner = null;
private string name = null;
private string description = null;
private object userData;
///
/// Description for accessibility
///
public string Description {
get {
return description;
}
set {
description = value;
}
}
///
/// [To be supplied.]
///
[DefaultValue(true)]
public bool Enabled {
get {
return enabled;
}
set {
if (enabled != value) {
enabled = value;
if ((int)(state & (LinkState.Hover | LinkState.Active)) != 0) {
state &= ~(LinkState.Hover | LinkState.Active);
if (owner != null) {
owner.OverrideCursor = null;
}
}
if (owner != null) {
owner.InvalidateLink(this);
}
}
}
}
///
/// [To be supplied.]
///
public int Length {
get {
if (length == -1) {
if (owner != null && !String.IsNullOrEmpty(owner.Text)) {
StringInfo stringInfo = new StringInfo(owner.Text);
return stringInfo.LengthInTextElements - Start;
}
else {
return 0;
}
}
return length;
}
set {
if (length != value) {
length = value;
if (owner != null) {
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
}
}
///
/// [To be supplied.]
///
[DefaultValue(null)]
public object LinkData {
get {
return linkData;
}
set {
linkData = value;
}
}
///
/// The LinkLabel object that owns this link.
///
internal LinkLabel Owner {
get {
return owner;
}
set {
owner = value;
}
}
internal LinkState State {
get {
return state;
}
set {
state = value;
}
}
///
/// The name for the link - useful for indexing by key.
///
[
DefaultValue(""),
SRCategory(SR.CatAppearance),
SRDescription(SR.TreeNodeNodeNameDescr)
]
public string Name {
get {
return name == null ? "" : name;
}
set {
this.name = value;
}
}
///
/// [To be supplied.]
///
public int Start {
get {
return start;
}
set {
if (start != value) {
start = value;
if (owner != null) {
owner.links.Sort(LinkLabel.linkComparer);
owner.InvalidateTextLayout();
owner.Invalidate();
}
}
}
}
///
/// [To be supplied.]
///
[DefaultValue(false)]
public bool Visited {
get {
return(State & LinkState.Visited) == LinkState.Visited;
}
set {
bool old = Visited;
if (value) {
State |= LinkState.Visited;
}
else {
State &= ~LinkState.Visited;
}
if (old != Visited && owner != null) {
owner.InvalidateLink(this);
}
}
}
internal Region VisualRegion {
get {
return visualRegion;
}
set {
visualRegion = value;
}
}
}
///
/// [To be supplied.]
///
private class LinkComparer : IComparer {
int IComparer.Compare(object link1, object link2) {
Debug.Assert(link1 != null && link2 != null, "Null objects sent for comparison");
int pos1 = ((Link)link1).Start;
int pos2 = ((Link)link2).Start;
return pos1 - pos2;
}
}
///
///
[System.Runtime.InteropServices.ComVisible(true)]
internal class LinkLabelAccessibleObject : LabelAccessibleObject {
///
///
public LinkLabelAccessibleObject(LinkLabel owner) : base(owner) {
}
///
///
public override AccessibleObject GetChild(int index) {
if (index >= 0 && index < ((LinkLabel)Owner).Links.Count) {
return new LinkAccessibleObject(((LinkLabel)Owner).Links[index]);
}
else {
return null;
}
}
public override System.Windows.Forms.AccessibleObject HitTest(int x, int y) {
Point p = Owner.PointToClient(new Point(x, y));
Link hit = ((LinkLabel)Owner).PointInLink(p.X, p.Y);
if (hit != null) {
return new LinkAccessibleObject(hit);
}
if (this.Bounds.Contains(x, y)) {
return this;
}
return null;
}
///
///
public override int GetChildCount() {
return((LinkLabel)Owner).Links.Count;
}
}
///
///
[System.Runtime.InteropServices.ComVisible(true)]
internal class LinkAccessibleObject : AccessibleObject {
private Link link;
public LinkAccessibleObject(Link link) : base() {
this.link = link;
}
public override Rectangle Bounds {
get {
Region region = link.VisualRegion;
Graphics g = null;
IntSecurity.ObjectFromWin32Handle.Assert();
try
{
g = Graphics.FromHwnd(link.Owner.Handle);
}
finally
{
CodeAccessPermission.RevertAssert();
}
// Make sure we have a region for this link
//
if (region == null) {
link.Owner.EnsureRun(g);
region = link.VisualRegion;
if (region == null) {
g.Dispose();
return Rectangle.Empty;
}
}
Rectangle rect;
try {
rect = Rectangle.Ceiling(region.GetBounds(g));
}
finally {
g.Dispose();
}
// Translate rect to screen coordinates
//
return link.Owner.RectangleToScreen(rect);
}
}
public override string DefaultAction {
get {
return SR.GetString(SR.AccessibleActionClick);
}
}
public override string Description {
get {
return link.Description;
}
}
public override string Name {
get {
string text = link.Owner.Text;
int charStart = LinkLabel.ConvertToCharIndex(link.Start, text);
int charEnd = LinkLabel.ConvertToCharIndex(link.Start + link.Length, text);
return text.Substring(charStart, charEnd - charStart);
}
set {
base.Name = value;
}
}
public override AccessibleObject Parent {
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
get {
return link.Owner.AccessibilityObject;
}
}
public override AccessibleRole Role {
get {
return AccessibleRole.Link;
}
}
public override AccessibleStates State {
get {
AccessibleStates state = AccessibleStates.Focusable;
// Selected state
//
if (link.Owner.FocusLink == link) {
state |= AccessibleStates.Focused;
}
return state;
}
}
public override string Value {
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
get {
return Name;
}
}
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.UnmanagedCode)]
public override void DoDefaultAction() {
link.Owner.OnLinkClicked(new LinkLabelLinkClickedEventArgs(link));
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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- ConfigXmlWhitespace.cs
- ExpressionConverter.cs
- StringAnimationBase.cs
- ActivityValidator.cs
- SqlTransaction.cs
- RangeValuePattern.cs
- RegexStringValidator.cs
- ObjectToken.cs
- _BasicClient.cs
- ScrollChrome.cs
- PropertyTabChangedEvent.cs
- FixedPosition.cs
- TextViewBase.cs
- SecurityPolicySection.cs
- PageClientProxyGenerator.cs
- _FixedSizeReader.cs
- WebHttpEndpointElement.cs
- WebServiceResponseDesigner.cs
- ForeignConstraint.cs
- RenderCapability.cs
- InertiaExpansionBehavior.cs
- DocumentationServerProtocol.cs
- Int16.cs
- AppDomainAttributes.cs
- Matrix3D.cs
- HttpBufferlessInputStream.cs
- ErrorEventArgs.cs
- TrackingProfile.cs
- Converter.cs
- StructuralType.cs
- NavigationWindowAutomationPeer.cs
- DbBuffer.cs
- WindowsPrincipal.cs
- COM2IManagedPerPropertyBrowsingHandler.cs
- TextEvent.cs
- XPathConvert.cs
- KeyboardNavigation.cs
- MediaTimeline.cs
- TdsValueSetter.cs
- MultipartContentParser.cs
- XPathExpr.cs
- SolidBrush.cs
- XPathArrayIterator.cs
- Odbc32.cs
- SqlBuffer.cs
- EdmFunctionAttribute.cs
- EntityTypeEmitter.cs
- XmlHierarchicalDataSourceView.cs
- SecureConversationVersion.cs
- X509ClientCertificateAuthenticationElement.cs
- WebRequestModuleElement.cs
- SqlDataSource.cs
- HttpHeaderCollection.cs
- WindowsEditBoxRange.cs
- Camera.cs
- EntityModelBuildProvider.cs
- ModuleElement.cs
- ClientSettingsSection.cs
- ProjectionPruner.cs
- shaperfactoryquerycachekey.cs
- GeneralTransform3DTo2D.cs
- JobStaple.cs
- LocalFileSettingsProvider.cs
- PtsHelper.cs
- AsyncResult.cs
- Int64.cs
- MappingException.cs
- SystemUdpStatistics.cs
- HtmlToClrEventProxy.cs
- DbDataRecord.cs
- ButtonFieldBase.cs
- TextAnchor.cs
- invalidudtexception.cs
- EditingCoordinator.cs
- CodeTypeDeclaration.cs
- ISFTagAndGuidCache.cs
- AbsoluteQuery.cs
- SizeF.cs
- EventHandlersStore.cs
- EventRecord.cs
- StorageModelBuildProvider.cs
- BaseCAMarshaler.cs
- ShellProvider.cs
- ProfileGroupSettingsCollection.cs
- ScrollBar.cs
- FormClosedEvent.cs
- ParenthesizePropertyNameAttribute.cs
- EventSetterHandlerConverter.cs
- ThreadStaticAttribute.cs
- CacheDependency.cs
- NonVisualControlAttribute.cs
- XmlTextReader.cs
- DesignTimeParseData.cs
- HttpException.cs
- XmlStreamStore.cs
- ChangeInterceptorAttribute.cs
- OverrideMode.cs
- LZCodec.cs
- SecurityRuntime.cs
- RoutedEventConverter.cs