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 / Parameter.cs / 1 / Parameter.cs
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Web.UI.WebControls {
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Globalization;
using System.Security.Permissions;
///
/// Represents a parameter to a DataSourceControl.
/// Parameters can be session variables, web request parameters, or of custom types.
///
[
DefaultProperty("DefaultValue"),
]
[AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
public class Parameter : ICloneable, IStateManager {
private ParameterCollection _owner;
private bool _tracking;
private StateBag _viewState;
///
/// Creates an instance of the Parameter class.
///
public Parameter() {
}
///
/// Creates an instance of the Parameter class with the specified parameter name.
///
public Parameter(string name) {
Name = name;
}
///
/// Creates an instance of the Parameter class with the specified parameter name and db type.
///
public Parameter(string name, DbType dbType) {
Name = name;
DbType = dbType;
}
///
/// Creates an instance of the Parameter class with the specified parameter name, db type, and default value.
///
public Parameter(string name, DbType dbType, string defaultValue) {
Name = name;
DbType = dbType;
DefaultValue = defaultValue;
}
///
/// Creates an instance of the Parameter class with the specified parameter name and type.
///
public Parameter(string name, TypeCode type) {
Name = name;
Type = type;
}
///
/// Creates an instance of the Parameter class with the specified parameter name, type, and default value.
///
public Parameter(string name, TypeCode type, string defaultValue) {
Name = name;
Type = type;
DefaultValue = defaultValue;
}
///
/// Used to clone a parameter.
///
protected Parameter(Parameter original) {
DefaultValue = original.DefaultValue;
Direction = original.Direction;
Name = original.Name;
ConvertEmptyStringToNull = original.ConvertEmptyStringToNull;
Size = original.Size;
Type = original.Type;
DbType = original.DbType;
}
///
/// Indicates whether the Parameter is tracking view state.
///
protected bool IsTrackingViewState {
get {
return _tracking;
}
}
///
/// Gets/sets the db type of the parameter's value.
/// When DbType is DbType.Object, the Type property will be used instead
///
[
DefaultValue(DbType.Object),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_DbType),
]
public DbType DbType {
get {
object o = ViewState["DbType"];
if (o == null)
return DbType.Object;
return (DbType)o;
}
set {
if (value < DbType.AnsiString || value > DbType.DateTimeOffset) {
throw new ArgumentOutOfRangeException("value");
}
if (DbType != value) {
ViewState["DbType"] = value;
OnParameterChanged();
}
}
}
///
/// The default value to use in GetValue() if it cannot obtain a value.
///
[
DefaultValue(null),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_DefaultValue),
]
public string DefaultValue {
get {
object o = ViewState["DefaultValue"];
return (o as string);
}
set {
if (DefaultValue != value) {
ViewState["DefaultValue"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the direction of the parameter.
///
[
DefaultValue(ParameterDirection.Input),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Direction),
]
public ParameterDirection Direction {
get {
object o = ViewState["Direction"];
if (o == null)
return ParameterDirection.Input;
return (ParameterDirection)o;
}
set {
if (Direction != value) {
ViewState["Direction"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the name of the parameter.
///
[
DefaultValue(""),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Name),
]
public string Name {
get {
object o = ViewState["Name"];
if (o == null)
return String.Empty;
return (string)o;
}
set {
if (Name != value) {
ViewState["Name"] = value;
OnParameterChanged();
}
}
}
///
/// Returns the value of parameter after converting it to the proper type.
///
[
Browsable(false),
]
internal object ParameterValue {
get {
return GetValue(ViewState["ParameterValue"], false);
}
}
public DbType GetDatabaseType() {
DbType dbType = DbType;
if (dbType == DbType.Object) {
return ConvertTypeCodeToDbType(Type);
}
if (Type != TypeCode.Empty) {
throw new InvalidOperationException(SR.GetString(SR.Parameter_TypeNotSupported, Name));
}
return dbType;
}
internal object GetValue(object value, bool ignoreNullableTypeChanges) {
DbType dbType = DbType;
if (dbType == DbType.Object) {
return GetValue(value, DefaultValue, Type, ConvertEmptyStringToNull, ignoreNullableTypeChanges);
}
if (Type != TypeCode.Empty) {
throw new InvalidOperationException(SR.GetString(SR.Parameter_TypeNotSupported, Name));
}
return GetValue(value, DefaultValue, dbType, ConvertEmptyStringToNull, ignoreNullableTypeChanges);
}
internal static object GetValue(object value, string defaultValue, DbType dbType, bool convertEmptyStringToNull,
bool ignoreNullableTypeChanges) {
// use the TypeCode conversion logic for Whidbey types.
if ((dbType != DbType.DateTimeOffset) && (dbType != DbType.Time) && (dbType != DbType.Guid)) {
TypeCode type = ConvertDbTypeToTypeCode(dbType);
return GetValue(value, defaultValue, type, convertEmptyStringToNull, ignoreNullableTypeChanges);
}
value = HandleNullValue(value, defaultValue, convertEmptyStringToNull);
if (value == null) {
return null;
}
// For ObjectDataSource we special-case Nullable and do nothing because these
// types will get converted when we actually call the method.
if (ignoreNullableTypeChanges && IsNullableType(value.GetType())) {
return value;
}
if (dbType == DbType.DateTimeOffset) {
if (value is DateTimeOffset) {
return value;
}
return DateTimeOffset.Parse(value.ToString(), CultureInfo.CurrentCulture);
}
else if (dbType == DbType.Time) {
if (value is TimeSpan) {
return value;
}
return TimeSpan.Parse(value.ToString());
}
else if (dbType == DbType.Guid) {
if (value is Guid) {
return value;
}
return new Guid(value.ToString());
}
Debug.Fail("Should never reach this point.");
return null;
}
internal static object GetValue(object value, string defaultValue, TypeCode type, bool convertEmptyStringToNull, bool ignoreNullableTypeChanges) {
// Convert.ChangeType() throws if you attempt to convert to DBNull, so we have to special case it.
if (type == TypeCode.DBNull) {
return DBNull.Value;
}
value = HandleNullValue(value, defaultValue, convertEmptyStringToNull);
if (value == null) {
return null;
}
if (type == TypeCode.Object || type == TypeCode.Empty) {
return value;
}
// For ObjectDataSource we special-case Nullable and do nothing because these
// types will get converted when we actually call the method.
if (ignoreNullableTypeChanges && IsNullableType(value.GetType())) {
return value;
}
return value = Convert.ChangeType(value, type, CultureInfo.CurrentCulture);;
}
private static object HandleNullValue(object value, string defaultValue, bool convertEmptyStringToNull) {
// Get the value and convert it to the default value if it is null
if (convertEmptyStringToNull) {
string stringValue = value as string;
if ((stringValue != null) && (stringValue.Length == 0)) {
value = null;
}
}
if (value == null) {
// Attempt to use the default value, but if it is null too, just return null immediately
if (convertEmptyStringToNull && String.IsNullOrEmpty(defaultValue)) {
defaultValue = null;
}
if (defaultValue == null) {
return null;
}
value = defaultValue;
}
return value;
}
private static bool IsNullableType(Type type) {
return type.IsGenericType && (type.GetGenericTypeDefinition() == typeof(Nullable<>));
}
///
/// Gets/sets the size of the parameter.
///
[
DefaultValue(0),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Size),
]
public int Size {
get {
object o = ViewState["Size"];
if (o == null)
return 0;
return (int)o;
}
set {
if (Size != value) {
ViewState["Size"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the type of the parameter's value.
///
[
DefaultValue(TypeCode.Empty),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Type),
]
public TypeCode Type {
get {
object o = ViewState["Type"];
if (o == null)
return TypeCode.Empty;
return (TypeCode)o;
}
set {
if (value < TypeCode.Empty || value > TypeCode.String) {
throw new ArgumentOutOfRangeException("value");
}
if (Type != value) {
ViewState["Type"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets whether an empty string should be treated as a null value. If this property is set to true
/// and the value is an empty string, the default value will be used.
///
[
DefaultValue(true),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_ConvertEmptyStringToNull),
]
public bool ConvertEmptyStringToNull {
get {
object o = ViewState["ConvertEmptyStringToNull"];
if (o == null)
return true;
return (bool)o;
}
set {
if (ConvertEmptyStringToNull != value) {
ViewState["ConvertEmptyStringToNull"] = value;
OnParameterChanged();
}
}
}
///
/// Indicates a dictionary of state information that allows you to save and restore
/// the state of a Parameter across multiple requests for the same page.
///
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden),
]
protected StateBag ViewState {
get {
if (_viewState == null) {
_viewState = new StateBag();
if (_tracking)
_viewState.TrackViewState();
}
return _viewState;
}
}
///
/// Creates a new Parameter that is a copy of this Parameter.
///
protected virtual Parameter Clone() {
return new Parameter(this);
}
public static TypeCode ConvertDbTypeToTypeCode(DbType dbType) {
switch (dbType) {
case DbType.AnsiString:
case DbType.AnsiStringFixedLength:
case DbType.String:
case DbType.StringFixedLength:
return TypeCode.String;
case DbType.Boolean:
return TypeCode.Boolean;
case DbType.Byte:
return TypeCode.Byte;
case DbType.VarNumeric: // ???
case DbType.Currency:
case DbType.Decimal:
return TypeCode.Decimal;
case DbType.Date:
case DbType.DateTime:
case DbType.DateTime2: // new Katmai type
case DbType.Time: // new Katmai type - no TypeCode for TimeSpan
return TypeCode.DateTime;
case DbType.Double:
return TypeCode.Double;
case DbType.Int16:
return TypeCode.Int16;
case DbType.Int32:
return TypeCode.Int32;
case DbType.Int64:
return TypeCode.Int64;
case DbType.SByte:
return TypeCode.SByte;
case DbType.Single:
return TypeCode.Single;
case DbType.UInt16:
return TypeCode.UInt16;
case DbType.UInt32:
return TypeCode.UInt32;
case DbType.UInt64:
return TypeCode.UInt64;
case DbType.Guid: // ???
case DbType.Binary:
case DbType.Object:
case DbType.DateTimeOffset: // new Katmai type - no TypeCode for DateTimeOffset
default:
return TypeCode.Object;
}
}
public static DbType ConvertTypeCodeToDbType(TypeCode typeCode) {
// no TypeCode equivalent for TimeSpan or DateTimeOffset
switch (typeCode) {
case TypeCode.Boolean:
return DbType.Boolean;
case TypeCode.Byte:
return DbType.Byte;
case TypeCode.Char:
return DbType.StringFixedLength; // ???
case TypeCode.DateTime: // Used for Date, DateTime and DateTime2 DbTypes
return DbType.DateTime;
case TypeCode.Decimal:
return DbType.Decimal;
case TypeCode.Double:
return DbType.Double;
case TypeCode.Int16:
return DbType.Int16;
case TypeCode.Int32:
return DbType.Int32;
case TypeCode.Int64:
return DbType.Int64;
case TypeCode.SByte:
return DbType.SByte;
case TypeCode.Single:
return DbType.Single;
case TypeCode.String:
return DbType.String;
case TypeCode.UInt16:
return DbType.UInt16;
case TypeCode.UInt32:
return DbType.UInt32;
case TypeCode.UInt64:
return DbType.UInt64;
case TypeCode.DBNull:
case TypeCode.Empty:
case TypeCode.Object:
default:
return DbType.Object;
}
}
///
/// Evaluates the parameter and returns the new value.
/// The control parameter is used to access the page's framework.
/// By default it returns the null, implying that the DefaultValue will
/// be the value.
///
protected virtual object Evaluate(HttpContext context, Control control) {
return null;
}
///
/// Loads view state.
///
protected virtual void LoadViewState(object savedState) {
if (savedState != null) {
ViewState.LoadViewState(savedState);
}
}
///
/// Raises the ParameterChanged event. This notifies a listener that it should re-evaluate the value.
///
protected void OnParameterChanged() {
if (_owner != null) {
_owner.CallOnParametersChanged();
}
}
///
/// Saves view state.
///
protected virtual object SaveViewState() {
return (_viewState != null) ? _viewState.SaveViewState() : null;
}
///
/// Tells the Parameter to record its entire state into view state.
///
protected internal virtual void SetDirty() {
ViewState.SetDirty(true);
}
///
/// Tells the Parameter the collection it belongs to
///
internal void SetOwner(ParameterCollection owner) {
_owner = owner;
}
///
/// Converts the Parameter to a string value.
///
public override string ToString() {
return this.Name;
}
///
/// Tells the Parameter to start tracking property changes.
///
protected virtual void TrackViewState() {
_tracking = true;
if (_viewState != null) {
_viewState.TrackViewState();
}
}
///
/// Updates the value of parameter.
/// If the value changed, this will raise the ParametersChanged event of the ParameterCollection it belongs to.
/// The control parameter is used to access the page's framework.
///
internal void UpdateValue(HttpContext context, Control control) {
object oldValue = ViewState["ParameterValue"];
object newValue = Evaluate(context, control);
ViewState["ParameterValue"] = newValue;
// If you have chains of dependency, like one control with a control parameter on another, and then a third with a control
// parameter on the second, the order in which the evaluations take place is non-deterministic and may create incorrect
// evaluation of parameters because all our evaluation happens during LoadComplete. The correct solution is to call DataBind
// on the third control when the second control's selected value changes. Hacky, but we don't support specifying dependency
// chains on data sources.
if ((newValue == null && oldValue != null) || (newValue != null && !newValue.Equals(oldValue))) {
OnParameterChanged();
}
}
#region Implementation of ICloneable
///
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Web.UI.WebControls {
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Globalization;
using System.Security.Permissions;
///
/// Represents a parameter to a DataSourceControl.
/// Parameters can be session variables, web request parameters, or of custom types.
///
[
DefaultProperty("DefaultValue"),
]
[AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
public class Parameter : ICloneable, IStateManager {
private ParameterCollection _owner;
private bool _tracking;
private StateBag _viewState;
///
/// Creates an instance of the Parameter class.
///
public Parameter() {
}
///
/// Creates an instance of the Parameter class with the specified parameter name.
///
public Parameter(string name) {
Name = name;
}
///
/// Creates an instance of the Parameter class with the specified parameter name and db type.
///
public Parameter(string name, DbType dbType) {
Name = name;
DbType = dbType;
}
///
/// Creates an instance of the Parameter class with the specified parameter name, db type, and default value.
///
public Parameter(string name, DbType dbType, string defaultValue) {
Name = name;
DbType = dbType;
DefaultValue = defaultValue;
}
///
/// Creates an instance of the Parameter class with the specified parameter name and type.
///
public Parameter(string name, TypeCode type) {
Name = name;
Type = type;
}
///
/// Creates an instance of the Parameter class with the specified parameter name, type, and default value.
///
public Parameter(string name, TypeCode type, string defaultValue) {
Name = name;
Type = type;
DefaultValue = defaultValue;
}
///
/// Used to clone a parameter.
///
protected Parameter(Parameter original) {
DefaultValue = original.DefaultValue;
Direction = original.Direction;
Name = original.Name;
ConvertEmptyStringToNull = original.ConvertEmptyStringToNull;
Size = original.Size;
Type = original.Type;
DbType = original.DbType;
}
///
/// Indicates whether the Parameter is tracking view state.
///
protected bool IsTrackingViewState {
get {
return _tracking;
}
}
///
/// Gets/sets the db type of the parameter's value.
/// When DbType is DbType.Object, the Type property will be used instead
///
[
DefaultValue(DbType.Object),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_DbType),
]
public DbType DbType {
get {
object o = ViewState["DbType"];
if (o == null)
return DbType.Object;
return (DbType)o;
}
set {
if (value < DbType.AnsiString || value > DbType.DateTimeOffset) {
throw new ArgumentOutOfRangeException("value");
}
if (DbType != value) {
ViewState["DbType"] = value;
OnParameterChanged();
}
}
}
///
/// The default value to use in GetValue() if it cannot obtain a value.
///
[
DefaultValue(null),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_DefaultValue),
]
public string DefaultValue {
get {
object o = ViewState["DefaultValue"];
return (o as string);
}
set {
if (DefaultValue != value) {
ViewState["DefaultValue"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the direction of the parameter.
///
[
DefaultValue(ParameterDirection.Input),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Direction),
]
public ParameterDirection Direction {
get {
object o = ViewState["Direction"];
if (o == null)
return ParameterDirection.Input;
return (ParameterDirection)o;
}
set {
if (Direction != value) {
ViewState["Direction"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the name of the parameter.
///
[
DefaultValue(""),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Name),
]
public string Name {
get {
object o = ViewState["Name"];
if (o == null)
return String.Empty;
return (string)o;
}
set {
if (Name != value) {
ViewState["Name"] = value;
OnParameterChanged();
}
}
}
///
/// Returns the value of parameter after converting it to the proper type.
///
[
Browsable(false),
]
internal object ParameterValue {
get {
return GetValue(ViewState["ParameterValue"], false);
}
}
public DbType GetDatabaseType() {
DbType dbType = DbType;
if (dbType == DbType.Object) {
return ConvertTypeCodeToDbType(Type);
}
if (Type != TypeCode.Empty) {
throw new InvalidOperationException(SR.GetString(SR.Parameter_TypeNotSupported, Name));
}
return dbType;
}
internal object GetValue(object value, bool ignoreNullableTypeChanges) {
DbType dbType = DbType;
if (dbType == DbType.Object) {
return GetValue(value, DefaultValue, Type, ConvertEmptyStringToNull, ignoreNullableTypeChanges);
}
if (Type != TypeCode.Empty) {
throw new InvalidOperationException(SR.GetString(SR.Parameter_TypeNotSupported, Name));
}
return GetValue(value, DefaultValue, dbType, ConvertEmptyStringToNull, ignoreNullableTypeChanges);
}
internal static object GetValue(object value, string defaultValue, DbType dbType, bool convertEmptyStringToNull,
bool ignoreNullableTypeChanges) {
// use the TypeCode conversion logic for Whidbey types.
if ((dbType != DbType.DateTimeOffset) && (dbType != DbType.Time) && (dbType != DbType.Guid)) {
TypeCode type = ConvertDbTypeToTypeCode(dbType);
return GetValue(value, defaultValue, type, convertEmptyStringToNull, ignoreNullableTypeChanges);
}
value = HandleNullValue(value, defaultValue, convertEmptyStringToNull);
if (value == null) {
return null;
}
// For ObjectDataSource we special-case Nullable and do nothing because these
// types will get converted when we actually call the method.
if (ignoreNullableTypeChanges && IsNullableType(value.GetType())) {
return value;
}
if (dbType == DbType.DateTimeOffset) {
if (value is DateTimeOffset) {
return value;
}
return DateTimeOffset.Parse(value.ToString(), CultureInfo.CurrentCulture);
}
else if (dbType == DbType.Time) {
if (value is TimeSpan) {
return value;
}
return TimeSpan.Parse(value.ToString());
}
else if (dbType == DbType.Guid) {
if (value is Guid) {
return value;
}
return new Guid(value.ToString());
}
Debug.Fail("Should never reach this point.");
return null;
}
internal static object GetValue(object value, string defaultValue, TypeCode type, bool convertEmptyStringToNull, bool ignoreNullableTypeChanges) {
// Convert.ChangeType() throws if you attempt to convert to DBNull, so we have to special case it.
if (type == TypeCode.DBNull) {
return DBNull.Value;
}
value = HandleNullValue(value, defaultValue, convertEmptyStringToNull);
if (value == null) {
return null;
}
if (type == TypeCode.Object || type == TypeCode.Empty) {
return value;
}
// For ObjectDataSource we special-case Nullable and do nothing because these
// types will get converted when we actually call the method.
if (ignoreNullableTypeChanges && IsNullableType(value.GetType())) {
return value;
}
return value = Convert.ChangeType(value, type, CultureInfo.CurrentCulture);;
}
private static object HandleNullValue(object value, string defaultValue, bool convertEmptyStringToNull) {
// Get the value and convert it to the default value if it is null
if (convertEmptyStringToNull) {
string stringValue = value as string;
if ((stringValue != null) && (stringValue.Length == 0)) {
value = null;
}
}
if (value == null) {
// Attempt to use the default value, but if it is null too, just return null immediately
if (convertEmptyStringToNull && String.IsNullOrEmpty(defaultValue)) {
defaultValue = null;
}
if (defaultValue == null) {
return null;
}
value = defaultValue;
}
return value;
}
private static bool IsNullableType(Type type) {
return type.IsGenericType && (type.GetGenericTypeDefinition() == typeof(Nullable<>));
}
///
/// Gets/sets the size of the parameter.
///
[
DefaultValue(0),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Size),
]
public int Size {
get {
object o = ViewState["Size"];
if (o == null)
return 0;
return (int)o;
}
set {
if (Size != value) {
ViewState["Size"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets the type of the parameter's value.
///
[
DefaultValue(TypeCode.Empty),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_Type),
]
public TypeCode Type {
get {
object o = ViewState["Type"];
if (o == null)
return TypeCode.Empty;
return (TypeCode)o;
}
set {
if (value < TypeCode.Empty || value > TypeCode.String) {
throw new ArgumentOutOfRangeException("value");
}
if (Type != value) {
ViewState["Type"] = value;
OnParameterChanged();
}
}
}
///
/// Gets/sets whether an empty string should be treated as a null value. If this property is set to true
/// and the value is an empty string, the default value will be used.
///
[
DefaultValue(true),
WebCategory("Parameter"),
WebSysDescription(SR.Parameter_ConvertEmptyStringToNull),
]
public bool ConvertEmptyStringToNull {
get {
object o = ViewState["ConvertEmptyStringToNull"];
if (o == null)
return true;
return (bool)o;
}
set {
if (ConvertEmptyStringToNull != value) {
ViewState["ConvertEmptyStringToNull"] = value;
OnParameterChanged();
}
}
}
///
/// Indicates a dictionary of state information that allows you to save and restore
/// the state of a Parameter across multiple requests for the same page.
///
[
Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden),
]
protected StateBag ViewState {
get {
if (_viewState == null) {
_viewState = new StateBag();
if (_tracking)
_viewState.TrackViewState();
}
return _viewState;
}
}
///
/// Creates a new Parameter that is a copy of this Parameter.
///
protected virtual Parameter Clone() {
return new Parameter(this);
}
public static TypeCode ConvertDbTypeToTypeCode(DbType dbType) {
switch (dbType) {
case DbType.AnsiString:
case DbType.AnsiStringFixedLength:
case DbType.String:
case DbType.StringFixedLength:
return TypeCode.String;
case DbType.Boolean:
return TypeCode.Boolean;
case DbType.Byte:
return TypeCode.Byte;
case DbType.VarNumeric: // ???
case DbType.Currency:
case DbType.Decimal:
return TypeCode.Decimal;
case DbType.Date:
case DbType.DateTime:
case DbType.DateTime2: // new Katmai type
case DbType.Time: // new Katmai type - no TypeCode for TimeSpan
return TypeCode.DateTime;
case DbType.Double:
return TypeCode.Double;
case DbType.Int16:
return TypeCode.Int16;
case DbType.Int32:
return TypeCode.Int32;
case DbType.Int64:
return TypeCode.Int64;
case DbType.SByte:
return TypeCode.SByte;
case DbType.Single:
return TypeCode.Single;
case DbType.UInt16:
return TypeCode.UInt16;
case DbType.UInt32:
return TypeCode.UInt32;
case DbType.UInt64:
return TypeCode.UInt64;
case DbType.Guid: // ???
case DbType.Binary:
case DbType.Object:
case DbType.DateTimeOffset: // new Katmai type - no TypeCode for DateTimeOffset
default:
return TypeCode.Object;
}
}
public static DbType ConvertTypeCodeToDbType(TypeCode typeCode) {
// no TypeCode equivalent for TimeSpan or DateTimeOffset
switch (typeCode) {
case TypeCode.Boolean:
return DbType.Boolean;
case TypeCode.Byte:
return DbType.Byte;
case TypeCode.Char:
return DbType.StringFixedLength; // ???
case TypeCode.DateTime: // Used for Date, DateTime and DateTime2 DbTypes
return DbType.DateTime;
case TypeCode.Decimal:
return DbType.Decimal;
case TypeCode.Double:
return DbType.Double;
case TypeCode.Int16:
return DbType.Int16;
case TypeCode.Int32:
return DbType.Int32;
case TypeCode.Int64:
return DbType.Int64;
case TypeCode.SByte:
return DbType.SByte;
case TypeCode.Single:
return DbType.Single;
case TypeCode.String:
return DbType.String;
case TypeCode.UInt16:
return DbType.UInt16;
case TypeCode.UInt32:
return DbType.UInt32;
case TypeCode.UInt64:
return DbType.UInt64;
case TypeCode.DBNull:
case TypeCode.Empty:
case TypeCode.Object:
default:
return DbType.Object;
}
}
///
/// Evaluates the parameter and returns the new value.
/// The control parameter is used to access the page's framework.
/// By default it returns the null, implying that the DefaultValue will
/// be the value.
///
protected virtual object Evaluate(HttpContext context, Control control) {
return null;
}
///
/// Loads view state.
///
protected virtual void LoadViewState(object savedState) {
if (savedState != null) {
ViewState.LoadViewState(savedState);
}
}
///
/// Raises the ParameterChanged event. This notifies a listener that it should re-evaluate the value.
///
protected void OnParameterChanged() {
if (_owner != null) {
_owner.CallOnParametersChanged();
}
}
///
/// Saves view state.
///
protected virtual object SaveViewState() {
return (_viewState != null) ? _viewState.SaveViewState() : null;
}
///
/// Tells the Parameter to record its entire state into view state.
///
protected internal virtual void SetDirty() {
ViewState.SetDirty(true);
}
///
/// Tells the Parameter the collection it belongs to
///
internal void SetOwner(ParameterCollection owner) {
_owner = owner;
}
///
/// Converts the Parameter to a string value.
///
public override string ToString() {
return this.Name;
}
///
/// Tells the Parameter to start tracking property changes.
///
protected virtual void TrackViewState() {
_tracking = true;
if (_viewState != null) {
_viewState.TrackViewState();
}
}
///
/// Updates the value of parameter.
/// If the value changed, this will raise the ParametersChanged event of the ParameterCollection it belongs to.
/// The control parameter is used to access the page's framework.
///
internal void UpdateValue(HttpContext context, Control control) {
object oldValue = ViewState["ParameterValue"];
object newValue = Evaluate(context, control);
ViewState["ParameterValue"] = newValue;
// If you have chains of dependency, like one control with a control parameter on another, and then a third with a control
// parameter on the second, the order in which the evaluations take place is non-deterministic and may create incorrect
// evaluation of parameters because all our evaluation happens during LoadComplete. The correct solution is to call DataBind
// on the third control when the second control's selected value changes. Hacky, but we don't support specifying dependency
// chains on data sources.
if ((newValue == null && oldValue != null) || (newValue != null && !newValue.Equals(oldValue))) {
OnParameterChanged();
}
}
#region Implementation of ICloneable
///
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- Stylesheet.cs
- ContextDataSourceView.cs
- ArrayListCollectionBase.cs
- SourceLineInfo.cs
- PathGeometry.cs
- ColumnMapCopier.cs
- DiscoveryOperationContextExtension.cs
- FileSecurity.cs
- TextSpanModifier.cs
- XmlArrayItemAttribute.cs
- WebControl.cs
- MenuItemBinding.cs
- ListCollectionView.cs
- future.cs
- FileIOPermission.cs
- SqlNodeAnnotation.cs
- HtmlTableRow.cs
- ISAPIWorkerRequest.cs
- ControlOperationBehavior.cs
- AnnotationStore.cs
- PreservationFileReader.cs
- ExceptionHelpers.cs
- ScriptComponentDescriptor.cs
- SecurityTokenValidationException.cs
- IndicCharClassifier.cs
- Int32KeyFrameCollection.cs
- DrawItemEvent.cs
- WorkflowTransactionService.cs
- SelectorAutomationPeer.cs
- ControlCachePolicy.cs
- AuthenticationSection.cs
- DesignerWebPartChrome.cs
- ToolStripRendererSwitcher.cs
- PixelFormats.cs
- SafeThreadHandle.cs
- ConfigurationPropertyCollection.cs
- AtomMaterializer.cs
- RegionInfo.cs
- XmlBoundElement.cs
- SafeCertificateStore.cs
- DayRenderEvent.cs
- BamlRecordWriter.cs
- DummyDataSource.cs
- ArglessEventHandlerProxy.cs
- CaseStatement.cs
- BindingExpressionBase.cs
- TrackingServices.cs
- ButtonStandardAdapter.cs
- ProgressBarHighlightConverter.cs
- RijndaelManaged.cs
- WarningException.cs
- Converter.cs
- ComplexTypeEmitter.cs
- DataTableReaderListener.cs
- VirtualPathProvider.cs
- CodeIdentifiers.cs
- XamlTreeBuilder.cs
- EntityDataSourceSelectedEventArgs.cs
- RegisteredScript.cs
- SystemPens.cs
- ExecutionScope.cs
- XmlSchemaProviderAttribute.cs
- MetadataImporter.cs
- EncryptedKeyIdentifierClause.cs
- PageFunction.cs
- DurableInstanceProvider.cs
- KeyEventArgs.cs
- Token.cs
- panel.cs
- WebRequestModuleElement.cs
- CustomCategoryAttribute.cs
- PathStreamGeometryContext.cs
- ExpressionBinding.cs
- TemplateAction.cs
- DynamicResourceExtension.cs
- DocumentGridContextMenu.cs
- InputLangChangeEvent.cs
- COM2AboutBoxPropertyDescriptor.cs
- XmlNode.cs
- _HelperAsyncResults.cs
- XmlDataSourceNodeDescriptor.cs
- PageTrueTypeFont.cs
- UTF7Encoding.cs
- ReadWriteControlDesigner.cs
- nulltextcontainer.cs
- COM2AboutBoxPropertyDescriptor.cs
- Identifier.cs
- MouseWheelEventArgs.cs
- RightsManagementInformation.cs
- ComboBox.cs
- FunctionCommandText.cs
- ModulesEntry.cs
- UnSafeCharBuffer.cs
- ColorTranslator.cs
- PreservationFileReader.cs
- EntityDataSourceState.cs
- DropShadowBitmapEffect.cs
- EmptyReadOnlyDictionaryInternal.cs
- CacheDependency.cs
- Hash.cs