MenuAdapter.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / whidbey / NetFXspW7 / ndp / fx / src / xsp / System / Web / UI / WebControls / Adapters / MenuAdapter.cs / 1 / MenuAdapter.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.WebControls.Adapters { 
 
    using System;
    using System.Diagnostics; 
    using System.Globalization;
    using System.Security.Permissions;
    using System.Text;
    using System.Web; 
    using System.Web.UI;
    using System.Web.UI.HtmlControls; 
    using System.Web.UI.WebControls; 

    [AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)] 
    [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
    public class MenuAdapter : WebControlAdapter, IPostBackEventHandler {

        private string _path; 
        private Panel _menuPanel;
        private int _currentAccessKey = 0; 
        private MenuItem _titleItem; 

        protected new Menu Control  { 
            get  {
                return (Menu) base.Control;
            }
        } 

        protected internal override void LoadAdapterControlState(Object state) { 
            if (state != null) { 
                Pair pairState = state as Pair;
                if (pairState != null) { 
                    base.LoadAdapterViewState(pairState.First);
                    _path = (string)pairState.Second;
                }
                else { 
                    base.LoadAdapterViewState(null);
                    _path = state as string; 
                } 
            }
        } 

        private string Escape(string path) {
            // This function escapes \\ so that they don't get replaced because of
            // a Netscape 4 bug. Other escapable characters will be escaped by . 
            // _ becomes __ and \\ becomes \_\
            StringBuilder b = null; 
 
            if (String.IsNullOrEmpty(path)) {
                return String.Empty; 
            }

            int startIndex = 0;
            int count = 0; 
            for (int i = 0; i < path.Length; i++) {
                switch (path[i]) { 
                    case '\\': 

                        if (i + 1 < path.Length && path[i + 1] == '\\') { 
                            if (b == null) {
                                b = new StringBuilder(path.Length + 5);
                            }
                            if (count > 0) { 
                                b.Append(path, startIndex, count);
                            } 
                            b.Append(@"\_\"); 
                            i++;
                            startIndex = i + 1; 
                            count = 0;
                        }
                        else {
                            count++; 
                        }
                        break; 
                    case '_': 
                        if (b == null) {
                            b = new StringBuilder(path.Length + 5); 
                        }

                        if (count > 0) {
                            b.Append(path, startIndex, count); 
                        }
 
                        b.Append("__"); 

                        startIndex = i + 1; 
                        count = 0;
                        break;
                    default:
                        count++; 
                        break;
                } 
            } 

            if (b == null) { 
                return path;
            }

            if (count > 0) { 
                b.Append(path, startIndex, count);
            } 
 
            return b.ToString();
        } 

        private string UnEscape(string path) {
            return path.Replace(@"\\", @"\").Replace(@"\_\", @"\\").Replace("__", "_");
        } 

        protected internal override void OnInit(EventArgs e) { 
            base.OnInit(e); 
            Control.Page.RegisterRequiresControlState(Control);
        } 

        protected internal override void OnPreRender(EventArgs e) {
            Control.OnPreRender(e, false);
        } 

        protected internal override object SaveAdapterControlState() { 
            object baseState = base.SaveAdapterViewState(); 

            if (baseState == null) { 
                if (_path != null) {
                    return _path;
                }
                else { 
                    return null;
                } 
            } 
            else {
                return new Pair(baseState, _path); 
            }
        }

        private void RenderBreak(HtmlTextWriter writer) { 
            if (Control.Orientation == Orientation.Vertical) {
                writer.WriteBreak(); 
            } 
            else {
                writer.Write(' '); 
            }
        }

        protected override void RenderBeginTag(HtmlTextWriter writer) { 
            Menu owner = Control;
            // skip link 
            if (owner.SkipLinkText.Length != 0) { 
                HyperLink skipLink = new HyperLink();
                skipLink.NavigateUrl = '#' + owner.ClientID + "_SkipLink"; 
                skipLink.ImageUrl = owner.SpacerImageUrl;
                skipLink.Text = owner.SkipLinkText;
                skipLink.Height = Unit.Pixel(1);
                skipLink.Width = Unit.Pixel(1); 
                skipLink.Page = Page;
                skipLink.RenderControl(writer); 
            } 
            _menuPanel = new Panel();
            _menuPanel.ID = owner.UniqueID; 
            _menuPanel.Page = Page;
            // Determine root menu style
            MenuItem titleItem;
            if (_path != null) { 
                titleItem = owner.Items.FindItem(_path.Split(TreeView.InternalPathSeparator), 0);
                _titleItem = titleItem; 
            } 
            else {
                titleItem = owner.RootItem; 
            }
            SubMenuStyle rootMenuStyle = owner.GetSubMenuStyle(titleItem);
            if (!rootMenuStyle.IsEmpty) {
                if (Page != null && Page.SupportsStyleSheets) { 
                    string styleClass = owner.GetSubMenuCssClassName(titleItem);
                    if (styleClass.Trim().Length > 0) { 
                        _menuPanel.CssClass = styleClass; 
                    }
                } 
                else {
                    _menuPanel.ApplyStyle(rootMenuStyle);
                }
            } 
            _menuPanel.Width = owner.Width;
            _menuPanel.Height = owner.Height; 
            _menuPanel.Enabled = owner.IsEnabled; 
            _menuPanel.RenderBeginTag(writer);
        } 

        protected override void RenderContents(HtmlTextWriter writer) {
            Menu owner = Control;
            int position = 0; 
            if (_titleItem != null) {
                if (_titleItem.Depth + 1 >= owner.MaximumDepth) { 
                    throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidDepth)); 
                }
                if (!_titleItem.IsEnabled) { 
                    throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidNavigation));
                }
                RenderItem(writer, _titleItem, position++);
                foreach (MenuItem child in _titleItem.ChildItems) { 
                    RenderItem(writer, child, position++);
                } 
                if (PageAdapter != null) { 
                    PageAdapter.RenderPostBackEvent(writer,
                                                    owner.UniqueID, 
                                                    "u",
                                                    SR.GetString(SR.MenuAdapter_Up),
                                                    SR.GetString(SR.MenuAdapter_UpOneLevel));
                } 
                else {
                    HyperLink link = new HyperLink(); 
                    link.NavigateUrl = Page.ClientScript.GetPostBackClientHyperlink(owner, "u"); 
                    link.Text = SR.GetString(SR.MenuAdapter_UpOneLevel);
                    link.Page = Page; 
                    link.RenderControl(writer);
                }
                return;
            } 
            else {
                position = 1; 
            } 
            _path = null;
            foreach(MenuItem child in owner.Items) { 
                RenderItem(writer, child, position++);
                if (owner.StaticDisplayLevels > 1 && child.ChildItems.Count > 0) {
                    RenderContentsRecursive(writer, child, 1, owner.StaticDisplayLevels);
                } 
            }
        } 
 
        private void RenderContentsRecursive(HtmlTextWriter writer, MenuItem parentItem, int depth, int maxDepth) {
            int position = 1; 
            foreach(MenuItem child in parentItem.ChildItems) {
                RenderItem(writer, child, position++);
                if (depth + 1 < maxDepth && child.ChildItems.Count > 0) {
                    RenderContentsRecursive(writer, child, depth + 1, maxDepth); 
                }
            } 
        } 

        protected override void RenderEndTag(HtmlTextWriter writer) { 
            _menuPanel.RenderEndTag(writer);
            // skip link
            if (Control.SkipLinkText.Length != 0) {
                HtmlAnchor skipAnchor = new HtmlAnchor(); 
                skipAnchor.Name = Control.ClientID + "_SkipLink";
                skipAnchor.Page = Page; 
                skipAnchor.RenderControl(writer); 
            }
        } 

        private void RenderExpand(HtmlTextWriter writer, MenuItem item, Menu owner) {
            string expandImageUrl = item.GetExpandImageUrl();
            if (expandImageUrl.Length > 0) { 
                Image expandImage = new Image();
                expandImage.ImageUrl = expandImageUrl; 
                expandImage.GenerateEmptyAlternateText = true; 
                if (item.Depth < owner.StaticDisplayLevels) {
 
                    expandImage.AlternateText = String.Format(
                        CultureInfo.CurrentCulture,
                        owner.StaticPopOutImageTextFormatString,
                        item.Text); 
                }
                else { 
 
                    expandImage.AlternateText = String.Format(
                        CultureInfo.CurrentCulture, 
                        owner.DynamicPopOutImageTextFormatString,
                        item.Text);
                }
                // expandImage.ImageAlign = ImageAlign.Right; 
                expandImage.ImageAlign = ImageAlign.AbsMiddle;
                expandImage.Page = Page; 
                expandImage.RenderControl(writer); 
            }
            else { 
                writer.Write(' ');
                if (item.Depth < owner.StaticDisplayLevels &&
                    owner.StaticPopOutImageTextFormatString.Length != 0) {
 
                    writer.Write(HttpUtility.HtmlEncode(String.Format(
                        CultureInfo.CurrentCulture, 
                        owner.StaticPopOutImageTextFormatString, 
                        item.Text)));
                } 
                else if (item.Depth >= owner.StaticDisplayLevels &&
                    owner.DynamicPopOutImageTextFormatString.Length != 0) {

                    writer.Write(HttpUtility.HtmlEncode(String.Format( 
                        CultureInfo.CurrentCulture,
                        owner.DynamicPopOutImageTextFormatString, 
                        item.Text))); 
                }
                else { 
                    writer.Write(HttpUtility.HtmlEncode(SR.GetString(SR.MenuAdapter_Expand, item.Text)));
                }
            }
        } 

        protected virtual internal void RenderItem(HtmlTextWriter writer, MenuItem item, int position) { 
            Menu owner = Control; 
            MenuItemStyle mergedStyle = owner.GetMenuItemStyle(item);
 
            string imageUrl = item.ImageUrl;
            int depth = item.Depth;
            int depthPlusOne = depth + 1;
            string toolTip = item.ToolTip; 
            string navigateUrl = item.NavigateUrl;
            string text = item.Text; 
            bool enabled = item.IsEnabled; 
            bool selectable = item.Selectable;
            MenuItemCollection childItems = item.ChildItems; 

            // Top separator
            string topSeparatorUrl = null;
            if (depth < owner.StaticDisplayLevels && owner.StaticTopSeparatorImageUrl.Length != 0) { 
                topSeparatorUrl = owner.StaticTopSeparatorImageUrl;
            } 
            else if (depth >= owner.StaticDisplayLevels && owner.DynamicTopSeparatorImageUrl.Length != 0) { 
                topSeparatorUrl = owner.DynamicTopSeparatorImageUrl;
            } 
            if (topSeparatorUrl != null) {
                Image separatorImage = new Image();
                separatorImage.ImageUrl = topSeparatorUrl;
                separatorImage.GenerateEmptyAlternateText = true; // XHtml compliance 
                separatorImage.Page = Page;
                separatorImage.RenderControl(writer); 
                RenderBreak(writer); 
            }
 
            // Don't render the top spacing if this is the first root item
            if ((mergedStyle != null) && !mergedStyle.ItemSpacing.IsEmpty &&
                ((_titleItem != null) || (position != 0))) {
                RenderSpace(writer, mergedStyle.ItemSpacing, owner.Orientation); 
            }
 
            // Item span 
            Panel itemPanel = new SpanPanel();
            itemPanel.Enabled = enabled; 
            itemPanel.Page = Page;

            // Apply styles
            if (Page != null && Page.SupportsStyleSheets) { 
                string styleClass = owner.GetCssClassName(item, false);
                if (styleClass.Trim().Length > 0) { 
                    itemPanel.CssClass = styleClass; 
                }
            } 
            else if (mergedStyle != null) {
                itemPanel.ApplyStyle(mergedStyle);
            }
 
            // Tooltip
            if (item.ToolTip.Length != 0) { 
                itemPanel.ToolTip = item.ToolTip; 
            }
 
            // Render item begin tag
            itemPanel.RenderBeginTag(writer);

            // If there is a navigation url on this item, set up the navigation stuff if: 
            // - the item is the current title item for this level
            // - the item has no children 
            // - the item is a static item of depth + 1 < StaticDisplayLevels 
            bool clickOpensThisNode = !((position == 0) ||
                                        (childItems.Count == 0) || 
                                        (depthPlusOne < owner.StaticDisplayLevels) ||
                                        (depthPlusOne >= owner.MaximumDepth));

            // Indent 
            if (position != 0 &&
                depth > 0 && 
                owner.StaticSubMenuIndent != Unit.Pixel(0) && 
                depth < owner.StaticDisplayLevels) {
                Image spacerImage = new Image(); 
                spacerImage.ImageUrl = owner.SpacerImageUrl;
                spacerImage.GenerateEmptyAlternateText = true; // XHtml compliance
                double indent = owner.StaticSubMenuIndent.Value * depth;
                if (indent < Unit.MaxValue) { 
                    spacerImage.Width = new Unit(indent, owner.StaticSubMenuIndent.Type);
                } 
                else { 
                    spacerImage.Width = new Unit(Unit.MaxValue, owner.StaticSubMenuIndent.Type);;
                } 
                spacerImage.Height = Unit.Pixel(1);
                spacerImage.Page = Page;
                spacerImage.RenderControl(writer);
            } 

            // Render out the item icon, if it is set and if the item is not templated (VSWhidbey 501618) 
            if (imageUrl.Length > 0 && item.NotTemplated()) { 
                Image newImage = new Image();
                newImage.ImageUrl = imageUrl; 
                if (toolTip.Length != 0) {
                    newImage.AlternateText = toolTip;
                }
                else { 
                    newImage.GenerateEmptyAlternateText = true; // XHtml compliance
                } 
                newImage.Page = Page; 
                newImage.RenderControl(writer);
                writer.Write(' '); 
            }

            bool applyInlineBorder;
            string linkClass; 
            if (Page != null && Page.SupportsStyleSheets) {
                linkClass = owner.GetCssClassName(item, true, out applyInlineBorder); 
            } 
            else {
                linkClass = String.Empty; 
                applyInlineBorder = false;
            }
            if (enabled && (clickOpensThisNode || selectable)) {
                string accessKey = owner.AccessKey; 
                string itemAccessKey = ((position == 0 || (position == 1 && depth == 0)) && accessKey.Length != 0) ?
                    accessKey : 
                    null; 
                if (navigateUrl.Length > 0 && !clickOpensThisNode) {
                    if (PageAdapter != null) { 
                        PageAdapter.RenderBeginHyperlink(writer,
                                                         owner.ResolveClientUrl(navigateUrl),
                                                         true,
                                                         SR.GetString(SR.Adapter_GoLabel), 
                                                         itemAccessKey != null ?
                                                          itemAccessKey : 
                                                          (_currentAccessKey < 10 ? 
                                                            (_currentAccessKey++).ToString(CultureInfo.InvariantCulture) :
                                                            null)); 
                        writer.Write(HttpUtility.HtmlEncode(item.FormattedText));
                        PageAdapter.RenderEndHyperlink(writer);
                    }
                    else { 
                        HyperLink link = new HyperLink();
                        link.NavigateUrl = owner.ResolveClientUrl(navigateUrl); 
                        string target = item.Target; 
                        if (String.IsNullOrEmpty(target)) {
                            target = owner.Target; 
                        }
                        if (!String.IsNullOrEmpty(target)) {
                            link.Target = target;
                        } 
                        link.AccessKey = itemAccessKey;
                        link.Page = Page; 
                        if (writer is Html32TextWriter) { 
                            link.RenderBeginTag(writer);
                            SpanPanel lbl = new SpanPanel(); 
                            lbl.Page = Page;
                            RenderStyle(writer, lbl, linkClass, mergedStyle, applyInlineBorder);
                            lbl.RenderBeginTag(writer);
                            item.RenderText(writer); 
                            lbl.RenderEndTag(writer);
                            link.RenderEndTag(writer); 
                        } 
                        else {
                            RenderStyle(writer, link, linkClass, mergedStyle, applyInlineBorder); 
                            link.RenderBeginTag(writer);
                            item.RenderText(writer);
                            link.RenderEndTag(writer);
                        } 
                    }
                } 
                // Otherwise, write out a postback that will open or select the item 
                else {
                    if (PageAdapter != null) { 
                        PageAdapter.RenderPostBackEvent(writer,
                                                        owner.UniqueID,
                                                        (clickOpensThisNode ? 'o' : 'b') +
                                                            Escape(item.InternalValuePath), 
                                                        SR.GetString(SR.Adapter_OKLabel),
                                                        item.FormattedText, 
                                                        null, 
                                                        itemAccessKey != null ?
                                                          itemAccessKey : 
                                                          (_currentAccessKey < 10 ?
                                                         (_currentAccessKey++).ToString(CultureInfo.InvariantCulture) :
                                                         null));
 
                        // Expand image
                        if (clickOpensThisNode) { 
                            RenderExpand(writer, item, owner); 
                        }
                    } 
                    else {
                        HyperLink link = new HyperLink();
                        link.NavigateUrl = Page.ClientScript.GetPostBackClientHyperlink(owner,
                            (clickOpensThisNode ? 'o' : 'b') + Escape(item.InternalValuePath), true); 
                        link.AccessKey = itemAccessKey;
                        link.Page = Page; 
                        if (writer is Html32TextWriter) { 
                            link.RenderBeginTag(writer);
                            SpanPanel lbl = new SpanPanel(); 
                            lbl.Page = Page;
                            RenderStyle(writer, lbl, linkClass, mergedStyle, applyInlineBorder);
                            lbl.RenderBeginTag(writer);
                            item.RenderText(writer); 
                            if (clickOpensThisNode) {
                                RenderExpand(writer, item, owner); 
                            } 
                            lbl.RenderEndTag(writer);
                            link.RenderEndTag(writer); 
                        }
                        else {
                            RenderStyle(writer, link, linkClass, mergedStyle, applyInlineBorder);
                            link.RenderBeginTag(writer); 
                            item.RenderText(writer);
                            if (clickOpensThisNode) { 
                                RenderExpand(writer, item, owner); 
                            }
                            link.RenderEndTag(writer); 
                        }
                    }
                }
            } 
            else {
                item.RenderText(writer); 
            } 
            itemPanel.RenderEndTag(writer);
 
            // Bottom (or right) item spacing
            RenderBreak(writer);
            if ((mergedStyle != null) && !mergedStyle.ItemSpacing.IsEmpty) {
                RenderSpace(writer, mergedStyle.ItemSpacing, owner.Orientation); 
            }
 
            // Bottom separator 
            string bottomSeparatorUrl = null;
            if (item.SeparatorImageUrl.Length != 0) { 
                bottomSeparatorUrl = item.SeparatorImageUrl;
            }
            else if ((depth < owner.StaticDisplayLevels) && (owner.StaticBottomSeparatorImageUrl.Length != 0)) {
                bottomSeparatorUrl = owner.StaticBottomSeparatorImageUrl; 
            }
            else if ((depth >= owner.StaticDisplayLevels) && (owner.DynamicBottomSeparatorImageUrl.Length != 0)) { 
                bottomSeparatorUrl = owner.DynamicBottomSeparatorImageUrl; 
            }
            if (bottomSeparatorUrl != null) { 
                Image separatorImage = new Image();
                separatorImage.ImageUrl = bottomSeparatorUrl;
                separatorImage.GenerateEmptyAlternateText = true; // XHtml compliance
                separatorImage.Page = Page; 
                separatorImage.RenderControl(writer);
                RenderBreak(writer); 
            } 
        }
 
        private void RenderSpace(HtmlTextWriter writer, Unit space, Orientation orientation) {
            Image spacerImage = new Image();
            spacerImage.ImageUrl = Control.SpacerImageUrl;
            spacerImage.GenerateEmptyAlternateText = true; // XHtml compliance 
            spacerImage.Page = Page;
            if (orientation == Orientation.Vertical) { 
                spacerImage.Height = space; 
                spacerImage.Width = Unit.Pixel(1);
                spacerImage.RenderControl(writer); 
                writer.WriteBreak();
            }
            else {
                spacerImage.Width = space; 
                spacerImage.Height = Unit.Pixel(1);
                spacerImage.RenderControl(writer); 
            } 
        }
 
        private void RenderStyle(HtmlTextWriter writer, WebControl control, string className, MenuItemStyle style, bool applyInlineBorder) {
            if (!String.IsNullOrEmpty(className)) {
                control.CssClass = className;
                if (applyInlineBorder) { 
                    // Add inline style to force the border to none to override any CssClass (VSWhidbey 336610)
                    writer.AddStyleAttribute(HtmlTextWriterStyle.BorderStyle, "none"); 
                    // And an inline font-size of 1em to avoid squaring relative font sizes by applying them twice 
                    writer.AddStyleAttribute(HtmlTextWriterStyle.FontSize, "1em");
                } 
            }
            else if (style != null) {
                control.ApplyStyle(style);
            } 
        }
 
        void IPostBackEventHandler.RaisePostBackEvent(string eventArgument) { 
            RaisePostBackEvent(eventArgument);
        } 

        protected virtual void RaisePostBackEvent(string eventArgument) {
            if (eventArgument.Length == 0) {
                return; 
            }
 
            // On postback, see what kind of event we received by checking the first character 
            char eventType = eventArgument[0];
 
            switch (eventType) {
                case 'o': {
                    // 'o' means that we're opening the secondary navigation for this node
                    // Get the path of the item specified in the eventArgument 
                    // The replace is to correct a Netscape 4 bug
                    string newPath = UnEscape(HttpUtility.UrlDecode(eventArgument.Substring(1))); 
                    // Check the number of separator characters in the argument (should not be more than the max depth) 
                    int matches = 0;
                    for (int i = 0; i < newPath.Length; i++) { 
                        if (newPath[i] == TreeView.InternalPathSeparator) {
                            if (++matches >= Control.MaximumDepth) {
                                throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidDepth));
                            } 
                        }
                    } 
                    // Check this item does have subitem 
                    // (otherwise, it should just be selected, not opened)
                    MenuItem item = Control.Items.FindItem(newPath.Split(TreeView.InternalPathSeparator), 0); 
                    if (item != null) {
                        if (item.ChildItems.Count > 0) {
                            _path = newPath;
                        } 
                        else {
                            Control.InternalRaisePostBackEvent(newPath); 
                        } 
                    }
                    break; 
                }
                case 'u' :
                    // 'u' means go up a level
                    if (_path != null) { 
                        // Find that item in the tree
                        MenuItem item = Control.Items.FindItem(_path.Split(TreeView.InternalPathSeparator), 0); 
                        if (item != null) { 
                            MenuItem parentItem = item.Parent;
                            if (parentItem != null && item.Depth + 1 > Control.StaticDisplayLevels) { 
                                _path = parentItem.InternalValuePath;
                            }
                            else {
                                _path = null; 
                            }
                        } 
                    } 
                    break;
 
                case 'b' :
                    // 'b' means bubble for to the control to handle
                    // The replace is to correct a Netscape 4 bug
                    Control.InternalRaisePostBackEvent( 
                        UnEscape(HttpUtility.UrlDecode(eventArgument.Substring(1))));
                    break; 
            } 
        }
 
        internal void SetPath(string path) {
            _path = path;
        }
 
        private class SpanPanel : Panel {
            protected override HtmlTextWriterTag TagKey { 
                get { 
                    return HtmlTextWriterTag.Span;
                } 
            }
        }
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.WebControls.Adapters { 
 
    using System;
    using System.Diagnostics; 
    using System.Globalization;
    using System.Security.Permissions;
    using System.Text;
    using System.Web; 
    using System.Web.UI;
    using System.Web.UI.HtmlControls; 
    using System.Web.UI.WebControls; 

    [AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)] 
    [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
    public class MenuAdapter : WebControlAdapter, IPostBackEventHandler {

        private string _path; 
        private Panel _menuPanel;
        private int _currentAccessKey = 0; 
        private MenuItem _titleItem; 

        protected new Menu Control  { 
            get  {
                return (Menu) base.Control;
            }
        } 

        protected internal override void LoadAdapterControlState(Object state) { 
            if (state != null) { 
                Pair pairState = state as Pair;
                if (pairState != null) { 
                    base.LoadAdapterViewState(pairState.First);
                    _path = (string)pairState.Second;
                }
                else { 
                    base.LoadAdapterViewState(null);
                    _path = state as string; 
                } 
            }
        } 

        private string Escape(string path) {
            // This function escapes \\ so that they don't get replaced because of
            // a Netscape 4 bug. Other escapable characters will be escaped by . 
            // _ becomes __ and \\ becomes \_\
            StringBuilder b = null; 
 
            if (String.IsNullOrEmpty(path)) {
                return String.Empty; 
            }

            int startIndex = 0;
            int count = 0; 
            for (int i = 0; i < path.Length; i++) {
                switch (path[i]) { 
                    case '\\': 

                        if (i + 1 < path.Length && path[i + 1] == '\\') { 
                            if (b == null) {
                                b = new StringBuilder(path.Length + 5);
                            }
                            if (count > 0) { 
                                b.Append(path, startIndex, count);
                            } 
                            b.Append(@"\_\"); 
                            i++;
                            startIndex = i + 1; 
                            count = 0;
                        }
                        else {
                            count++; 
                        }
                        break; 
                    case '_': 
                        if (b == null) {
                            b = new StringBuilder(path.Length + 5); 
                        }

                        if (count > 0) {
                            b.Append(path, startIndex, count); 
                        }
 
                        b.Append("__"); 

                        startIndex = i + 1; 
                        count = 0;
                        break;
                    default:
                        count++; 
                        break;
                } 
            } 

            if (b == null) { 
                return path;
            }

            if (count > 0) { 
                b.Append(path, startIndex, count);
            } 
 
            return b.ToString();
        } 

        private string UnEscape(string path) {
            return path.Replace(@"\\", @"\").Replace(@"\_\", @"\\").Replace("__", "_");
        } 

        protected internal override void OnInit(EventArgs e) { 
            base.OnInit(e); 
            Control.Page.RegisterRequiresControlState(Control);
        } 

        protected internal override void OnPreRender(EventArgs e) {
            Control.OnPreRender(e, false);
        } 

        protected internal override object SaveAdapterControlState() { 
            object baseState = base.SaveAdapterViewState(); 

            if (baseState == null) { 
                if (_path != null) {
                    return _path;
                }
                else { 
                    return null;
                } 
            } 
            else {
                return new Pair(baseState, _path); 
            }
        }

        private void RenderBreak(HtmlTextWriter writer) { 
            if (Control.Orientation == Orientation.Vertical) {
                writer.WriteBreak(); 
            } 
            else {
                writer.Write(' '); 
            }
        }

        protected override void RenderBeginTag(HtmlTextWriter writer) { 
            Menu owner = Control;
            // skip link 
            if (owner.SkipLinkText.Length != 0) { 
                HyperLink skipLink = new HyperLink();
                skipLink.NavigateUrl = '#' + owner.ClientID + "_SkipLink"; 
                skipLink.ImageUrl = owner.SpacerImageUrl;
                skipLink.Text = owner.SkipLinkText;
                skipLink.Height = Unit.Pixel(1);
                skipLink.Width = Unit.Pixel(1); 
                skipLink.Page = Page;
                skipLink.RenderControl(writer); 
            } 
            _menuPanel = new Panel();
            _menuPanel.ID = owner.UniqueID; 
            _menuPanel.Page = Page;
            // Determine root menu style
            MenuItem titleItem;
            if (_path != null) { 
                titleItem = owner.Items.FindItem(_path.Split(TreeView.InternalPathSeparator), 0);
                _titleItem = titleItem; 
            } 
            else {
                titleItem = owner.RootItem; 
            }
            SubMenuStyle rootMenuStyle = owner.GetSubMenuStyle(titleItem);
            if (!rootMenuStyle.IsEmpty) {
                if (Page != null && Page.SupportsStyleSheets) { 
                    string styleClass = owner.GetSubMenuCssClassName(titleItem);
                    if (styleClass.Trim().Length > 0) { 
                        _menuPanel.CssClass = styleClass; 
                    }
                } 
                else {
                    _menuPanel.ApplyStyle(rootMenuStyle);
                }
            } 
            _menuPanel.Width = owner.Width;
            _menuPanel.Height = owner.Height; 
            _menuPanel.Enabled = owner.IsEnabled; 
            _menuPanel.RenderBeginTag(writer);
        } 

        protected override void RenderContents(HtmlTextWriter writer) {
            Menu owner = Control;
            int position = 0; 
            if (_titleItem != null) {
                if (_titleItem.Depth + 1 >= owner.MaximumDepth) { 
                    throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidDepth)); 
                }
                if (!_titleItem.IsEnabled) { 
                    throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidNavigation));
                }
                RenderItem(writer, _titleItem, position++);
                foreach (MenuItem child in _titleItem.ChildItems) { 
                    RenderItem(writer, child, position++);
                } 
                if (PageAdapter != null) { 
                    PageAdapter.RenderPostBackEvent(writer,
                                                    owner.UniqueID, 
                                                    "u",
                                                    SR.GetString(SR.MenuAdapter_Up),
                                                    SR.GetString(SR.MenuAdapter_UpOneLevel));
                } 
                else {
                    HyperLink link = new HyperLink(); 
                    link.NavigateUrl = Page.ClientScript.GetPostBackClientHyperlink(owner, "u"); 
                    link.Text = SR.GetString(SR.MenuAdapter_UpOneLevel);
                    link.Page = Page; 
                    link.RenderControl(writer);
                }
                return;
            } 
            else {
                position = 1; 
            } 
            _path = null;
            foreach(MenuItem child in owner.Items) { 
                RenderItem(writer, child, position++);
                if (owner.StaticDisplayLevels > 1 && child.ChildItems.Count > 0) {
                    RenderContentsRecursive(writer, child, 1, owner.StaticDisplayLevels);
                } 
            }
        } 
 
        private void RenderContentsRecursive(HtmlTextWriter writer, MenuItem parentItem, int depth, int maxDepth) {
            int position = 1; 
            foreach(MenuItem child in parentItem.ChildItems) {
                RenderItem(writer, child, position++);
                if (depth + 1 < maxDepth && child.ChildItems.Count > 0) {
                    RenderContentsRecursive(writer, child, depth + 1, maxDepth); 
                }
            } 
        } 

        protected override void RenderEndTag(HtmlTextWriter writer) { 
            _menuPanel.RenderEndTag(writer);
            // skip link
            if (Control.SkipLinkText.Length != 0) {
                HtmlAnchor skipAnchor = new HtmlAnchor(); 
                skipAnchor.Name = Control.ClientID + "_SkipLink";
                skipAnchor.Page = Page; 
                skipAnchor.RenderControl(writer); 
            }
        } 

        private void RenderExpand(HtmlTextWriter writer, MenuItem item, Menu owner) {
            string expandImageUrl = item.GetExpandImageUrl();
            if (expandImageUrl.Length > 0) { 
                Image expandImage = new Image();
                expandImage.ImageUrl = expandImageUrl; 
                expandImage.GenerateEmptyAlternateText = true; 
                if (item.Depth < owner.StaticDisplayLevels) {
 
                    expandImage.AlternateText = String.Format(
                        CultureInfo.CurrentCulture,
                        owner.StaticPopOutImageTextFormatString,
                        item.Text); 
                }
                else { 
 
                    expandImage.AlternateText = String.Format(
                        CultureInfo.CurrentCulture, 
                        owner.DynamicPopOutImageTextFormatString,
                        item.Text);
                }
                // expandImage.ImageAlign = ImageAlign.Right; 
                expandImage.ImageAlign = ImageAlign.AbsMiddle;
                expandImage.Page = Page; 
                expandImage.RenderControl(writer); 
            }
            else { 
                writer.Write(' ');
                if (item.Depth < owner.StaticDisplayLevels &&
                    owner.StaticPopOutImageTextFormatString.Length != 0) {
 
                    writer.Write(HttpUtility.HtmlEncode(String.Format(
                        CultureInfo.CurrentCulture, 
                        owner.StaticPopOutImageTextFormatString, 
                        item.Text)));
                } 
                else if (item.Depth >= owner.StaticDisplayLevels &&
                    owner.DynamicPopOutImageTextFormatString.Length != 0) {

                    writer.Write(HttpUtility.HtmlEncode(String.Format( 
                        CultureInfo.CurrentCulture,
                        owner.DynamicPopOutImageTextFormatString, 
                        item.Text))); 
                }
                else { 
                    writer.Write(HttpUtility.HtmlEncode(SR.GetString(SR.MenuAdapter_Expand, item.Text)));
                }
            }
        } 

        protected virtual internal void RenderItem(HtmlTextWriter writer, MenuItem item, int position) { 
            Menu owner = Control; 
            MenuItemStyle mergedStyle = owner.GetMenuItemStyle(item);
 
            string imageUrl = item.ImageUrl;
            int depth = item.Depth;
            int depthPlusOne = depth + 1;
            string toolTip = item.ToolTip; 
            string navigateUrl = item.NavigateUrl;
            string text = item.Text; 
            bool enabled = item.IsEnabled; 
            bool selectable = item.Selectable;
            MenuItemCollection childItems = item.ChildItems; 

            // Top separator
            string topSeparatorUrl = null;
            if (depth < owner.StaticDisplayLevels && owner.StaticTopSeparatorImageUrl.Length != 0) { 
                topSeparatorUrl = owner.StaticTopSeparatorImageUrl;
            } 
            else if (depth >= owner.StaticDisplayLevels && owner.DynamicTopSeparatorImageUrl.Length != 0) { 
                topSeparatorUrl = owner.DynamicTopSeparatorImageUrl;
            } 
            if (topSeparatorUrl != null) {
                Image separatorImage = new Image();
                separatorImage.ImageUrl = topSeparatorUrl;
                separatorImage.GenerateEmptyAlternateText = true; // XHtml compliance 
                separatorImage.Page = Page;
                separatorImage.RenderControl(writer); 
                RenderBreak(writer); 
            }
 
            // Don't render the top spacing if this is the first root item
            if ((mergedStyle != null) && !mergedStyle.ItemSpacing.IsEmpty &&
                ((_titleItem != null) || (position != 0))) {
                RenderSpace(writer, mergedStyle.ItemSpacing, owner.Orientation); 
            }
 
            // Item span 
            Panel itemPanel = new SpanPanel();
            itemPanel.Enabled = enabled; 
            itemPanel.Page = Page;

            // Apply styles
            if (Page != null && Page.SupportsStyleSheets) { 
                string styleClass = owner.GetCssClassName(item, false);
                if (styleClass.Trim().Length > 0) { 
                    itemPanel.CssClass = styleClass; 
                }
            } 
            else if (mergedStyle != null) {
                itemPanel.ApplyStyle(mergedStyle);
            }
 
            // Tooltip
            if (item.ToolTip.Length != 0) { 
                itemPanel.ToolTip = item.ToolTip; 
            }
 
            // Render item begin tag
            itemPanel.RenderBeginTag(writer);

            // If there is a navigation url on this item, set up the navigation stuff if: 
            // - the item is the current title item for this level
            // - the item has no children 
            // - the item is a static item of depth + 1 < StaticDisplayLevels 
            bool clickOpensThisNode = !((position == 0) ||
                                        (childItems.Count == 0) || 
                                        (depthPlusOne < owner.StaticDisplayLevels) ||
                                        (depthPlusOne >= owner.MaximumDepth));

            // Indent 
            if (position != 0 &&
                depth > 0 && 
                owner.StaticSubMenuIndent != Unit.Pixel(0) && 
                depth < owner.StaticDisplayLevels) {
                Image spacerImage = new Image(); 
                spacerImage.ImageUrl = owner.SpacerImageUrl;
                spacerImage.GenerateEmptyAlternateText = true; // XHtml compliance
                double indent = owner.StaticSubMenuIndent.Value * depth;
                if (indent < Unit.MaxValue) { 
                    spacerImage.Width = new Unit(indent, owner.StaticSubMenuIndent.Type);
                } 
                else { 
                    spacerImage.Width = new Unit(Unit.MaxValue, owner.StaticSubMenuIndent.Type);;
                } 
                spacerImage.Height = Unit.Pixel(1);
                spacerImage.Page = Page;
                spacerImage.RenderControl(writer);
            } 

            // Render out the item icon, if it is set and if the item is not templated (VSWhidbey 501618) 
            if (imageUrl.Length > 0 && item.NotTemplated()) { 
                Image newImage = new Image();
                newImage.ImageUrl = imageUrl; 
                if (toolTip.Length != 0) {
                    newImage.AlternateText = toolTip;
                }
                else { 
                    newImage.GenerateEmptyAlternateText = true; // XHtml compliance
                } 
                newImage.Page = Page; 
                newImage.RenderControl(writer);
                writer.Write(' '); 
            }

            bool applyInlineBorder;
            string linkClass; 
            if (Page != null && Page.SupportsStyleSheets) {
                linkClass = owner.GetCssClassName(item, true, out applyInlineBorder); 
            } 
            else {
                linkClass = String.Empty; 
                applyInlineBorder = false;
            }
            if (enabled && (clickOpensThisNode || selectable)) {
                string accessKey = owner.AccessKey; 
                string itemAccessKey = ((position == 0 || (position == 1 && depth == 0)) && accessKey.Length != 0) ?
                    accessKey : 
                    null; 
                if (navigateUrl.Length > 0 && !clickOpensThisNode) {
                    if (PageAdapter != null) { 
                        PageAdapter.RenderBeginHyperlink(writer,
                                                         owner.ResolveClientUrl(navigateUrl),
                                                         true,
                                                         SR.GetString(SR.Adapter_GoLabel), 
                                                         itemAccessKey != null ?
                                                          itemAccessKey : 
                                                          (_currentAccessKey < 10 ? 
                                                            (_currentAccessKey++).ToString(CultureInfo.InvariantCulture) :
                                                            null)); 
                        writer.Write(HttpUtility.HtmlEncode(item.FormattedText));
                        PageAdapter.RenderEndHyperlink(writer);
                    }
                    else { 
                        HyperLink link = new HyperLink();
                        link.NavigateUrl = owner.ResolveClientUrl(navigateUrl); 
                        string target = item.Target; 
                        if (String.IsNullOrEmpty(target)) {
                            target = owner.Target; 
                        }
                        if (!String.IsNullOrEmpty(target)) {
                            link.Target = target;
                        } 
                        link.AccessKey = itemAccessKey;
                        link.Page = Page; 
                        if (writer is Html32TextWriter) { 
                            link.RenderBeginTag(writer);
                            SpanPanel lbl = new SpanPanel(); 
                            lbl.Page = Page;
                            RenderStyle(writer, lbl, linkClass, mergedStyle, applyInlineBorder);
                            lbl.RenderBeginTag(writer);
                            item.RenderText(writer); 
                            lbl.RenderEndTag(writer);
                            link.RenderEndTag(writer); 
                        } 
                        else {
                            RenderStyle(writer, link, linkClass, mergedStyle, applyInlineBorder); 
                            link.RenderBeginTag(writer);
                            item.RenderText(writer);
                            link.RenderEndTag(writer);
                        } 
                    }
                } 
                // Otherwise, write out a postback that will open or select the item 
                else {
                    if (PageAdapter != null) { 
                        PageAdapter.RenderPostBackEvent(writer,
                                                        owner.UniqueID,
                                                        (clickOpensThisNode ? 'o' : 'b') +
                                                            Escape(item.InternalValuePath), 
                                                        SR.GetString(SR.Adapter_OKLabel),
                                                        item.FormattedText, 
                                                        null, 
                                                        itemAccessKey != null ?
                                                          itemAccessKey : 
                                                          (_currentAccessKey < 10 ?
                                                         (_currentAccessKey++).ToString(CultureInfo.InvariantCulture) :
                                                         null));
 
                        // Expand image
                        if (clickOpensThisNode) { 
                            RenderExpand(writer, item, owner); 
                        }
                    } 
                    else {
                        HyperLink link = new HyperLink();
                        link.NavigateUrl = Page.ClientScript.GetPostBackClientHyperlink(owner,
                            (clickOpensThisNode ? 'o' : 'b') + Escape(item.InternalValuePath), true); 
                        link.AccessKey = itemAccessKey;
                        link.Page = Page; 
                        if (writer is Html32TextWriter) { 
                            link.RenderBeginTag(writer);
                            SpanPanel lbl = new SpanPanel(); 
                            lbl.Page = Page;
                            RenderStyle(writer, lbl, linkClass, mergedStyle, applyInlineBorder);
                            lbl.RenderBeginTag(writer);
                            item.RenderText(writer); 
                            if (clickOpensThisNode) {
                                RenderExpand(writer, item, owner); 
                            } 
                            lbl.RenderEndTag(writer);
                            link.RenderEndTag(writer); 
                        }
                        else {
                            RenderStyle(writer, link, linkClass, mergedStyle, applyInlineBorder);
                            link.RenderBeginTag(writer); 
                            item.RenderText(writer);
                            if (clickOpensThisNode) { 
                                RenderExpand(writer, item, owner); 
                            }
                            link.RenderEndTag(writer); 
                        }
                    }
                }
            } 
            else {
                item.RenderText(writer); 
            } 
            itemPanel.RenderEndTag(writer);
 
            // Bottom (or right) item spacing
            RenderBreak(writer);
            if ((mergedStyle != null) && !mergedStyle.ItemSpacing.IsEmpty) {
                RenderSpace(writer, mergedStyle.ItemSpacing, owner.Orientation); 
            }
 
            // Bottom separator 
            string bottomSeparatorUrl = null;
            if (item.SeparatorImageUrl.Length != 0) { 
                bottomSeparatorUrl = item.SeparatorImageUrl;
            }
            else if ((depth < owner.StaticDisplayLevels) && (owner.StaticBottomSeparatorImageUrl.Length != 0)) {
                bottomSeparatorUrl = owner.StaticBottomSeparatorImageUrl; 
            }
            else if ((depth >= owner.StaticDisplayLevels) && (owner.DynamicBottomSeparatorImageUrl.Length != 0)) { 
                bottomSeparatorUrl = owner.DynamicBottomSeparatorImageUrl; 
            }
            if (bottomSeparatorUrl != null) { 
                Image separatorImage = new Image();
                separatorImage.ImageUrl = bottomSeparatorUrl;
                separatorImage.GenerateEmptyAlternateText = true; // XHtml compliance
                separatorImage.Page = Page; 
                separatorImage.RenderControl(writer);
                RenderBreak(writer); 
            } 
        }
 
        private void RenderSpace(HtmlTextWriter writer, Unit space, Orientation orientation) {
            Image spacerImage = new Image();
            spacerImage.ImageUrl = Control.SpacerImageUrl;
            spacerImage.GenerateEmptyAlternateText = true; // XHtml compliance 
            spacerImage.Page = Page;
            if (orientation == Orientation.Vertical) { 
                spacerImage.Height = space; 
                spacerImage.Width = Unit.Pixel(1);
                spacerImage.RenderControl(writer); 
                writer.WriteBreak();
            }
            else {
                spacerImage.Width = space; 
                spacerImage.Height = Unit.Pixel(1);
                spacerImage.RenderControl(writer); 
            } 
        }
 
        private void RenderStyle(HtmlTextWriter writer, WebControl control, string className, MenuItemStyle style, bool applyInlineBorder) {
            if (!String.IsNullOrEmpty(className)) {
                control.CssClass = className;
                if (applyInlineBorder) { 
                    // Add inline style to force the border to none to override any CssClass (VSWhidbey 336610)
                    writer.AddStyleAttribute(HtmlTextWriterStyle.BorderStyle, "none"); 
                    // And an inline font-size of 1em to avoid squaring relative font sizes by applying them twice 
                    writer.AddStyleAttribute(HtmlTextWriterStyle.FontSize, "1em");
                } 
            }
            else if (style != null) {
                control.ApplyStyle(style);
            } 
        }
 
        void IPostBackEventHandler.RaisePostBackEvent(string eventArgument) { 
            RaisePostBackEvent(eventArgument);
        } 

        protected virtual void RaisePostBackEvent(string eventArgument) {
            if (eventArgument.Length == 0) {
                return; 
            }
 
            // On postback, see what kind of event we received by checking the first character 
            char eventType = eventArgument[0];
 
            switch (eventType) {
                case 'o': {
                    // 'o' means that we're opening the secondary navigation for this node
                    // Get the path of the item specified in the eventArgument 
                    // The replace is to correct a Netscape 4 bug
                    string newPath = UnEscape(HttpUtility.UrlDecode(eventArgument.Substring(1))); 
                    // Check the number of separator characters in the argument (should not be more than the max depth) 
                    int matches = 0;
                    for (int i = 0; i < newPath.Length; i++) { 
                        if (newPath[i] == TreeView.InternalPathSeparator) {
                            if (++matches >= Control.MaximumDepth) {
                                throw new InvalidOperationException(SR.GetString(SR.Menu_InvalidDepth));
                            } 
                        }
                    } 
                    // Check this item does have subitem 
                    // (otherwise, it should just be selected, not opened)
                    MenuItem item = Control.Items.FindItem(newPath.Split(TreeView.InternalPathSeparator), 0); 
                    if (item != null) {
                        if (item.ChildItems.Count > 0) {
                            _path = newPath;
                        } 
                        else {
                            Control.InternalRaisePostBackEvent(newPath); 
                        } 
                    }
                    break; 
                }
                case 'u' :
                    // 'u' means go up a level
                    if (_path != null) { 
                        // Find that item in the tree
                        MenuItem item = Control.Items.FindItem(_path.Split(TreeView.InternalPathSeparator), 0); 
                        if (item != null) { 
                            MenuItem parentItem = item.Parent;
                            if (parentItem != null && item.Depth + 1 > Control.StaticDisplayLevels) { 
                                _path = parentItem.InternalValuePath;
                            }
                            else {
                                _path = null; 
                            }
                        } 
                    } 
                    break;
 
                case 'b' :
                    // 'b' means bubble for to the control to handle
                    // The replace is to correct a Netscape 4 bug
                    Control.InternalRaisePostBackEvent( 
                        UnEscape(HttpUtility.UrlDecode(eventArgument.Substring(1))));
                    break; 
            } 
        }
 
        internal void SetPath(string path) {
            _path = path;
        }
 
        private class SpanPanel : Panel {
            protected override HtmlTextWriterTag TagKey { 
                get { 
                    return HtmlTextWriterTag.Span;
                } 
            }
        }
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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