|
//------------------------------------------------------------------------------
// <copyright file="HtmlTextArea.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
/*
* HtmlTextArea.cs
*
* Copyright (c) 2000 Microsoft Corporation
*/
namespace System.Web.UI.HtmlControls {
using System.ComponentModel;
using System;
using System.Collections;
using System.Collections.Specialized;
using System.Web;
using System.Web.UI;
using System.Globalization;
using System.Security.Permissions;
/// <devdoc>
/// <para>Defines the methods, properties, and events for the
/// <see cref='System.Web.UI.HtmlControls.HtmlTextArea'/>
/// class that
/// allows programmatic access to the HTML <textarea>.</para>
/// </devdoc>
[
DefaultEvent("ServerChange"),
SupportsEventValidation,
ValidationProperty("Value")
]
public class HtmlTextArea : HtmlContainerControl, IPostBackDataHandler {
private static readonly object EventServerChange = new object();
/*
* Creates an intrinsic Html TEXTAREA control.
*/
/// <devdoc>
/// Initializes a new instance of the <see cref='System.Web.UI.HtmlControls.HtmlTextArea'/> class.
/// </devdoc>
public HtmlTextArea() : base("textarea") {
}
/*
* The property for the number of columns to display.
*/
/// <devdoc>
/// <para> Indicates the display width (in characters) of the
/// text area.</para>
/// </devdoc>
[
WebCategory("Appearance"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public int Cols {
get {
string s = Attributes["cols"];
return((s != null) ? Int32.Parse(s, CultureInfo.InvariantCulture) : -1);
}
set {
Attributes["cols"] = MapIntegerAttributeToString(value);
}
}
/*
* Name property.
*/
/// <devdoc>
/// <para>
/// Gets the value of the HTML
/// Name attribute that will be rendered to the browser.
/// </para>
/// </devdoc>
[
WebCategory("Behavior"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public virtual string Name {
get {
return UniqueID;
//string s = Attributes["name"];
//return ((s != null) ? s : "");
}
set {
//Attributes["name"] = MapStringAttributeToString(value);
}
}
// Value that gets rendered for the Name attribute
internal string RenderedNameAttribute {
get {
return Name;
//string name = Name;
//if (name.Length == 0)
// return UniqueID;
//return name;
}
}
/*
* The property for the number of rows to display.
*/
/// <devdoc>
/// <para>Gets or sets the display height (in rows) of the text area.</para>
/// </devdoc>
[
WebCategory("Appearance"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public int Rows {
get {
string s = Attributes["rows"];
return((s != null) ? Int32.Parse(s, CultureInfo.InvariantCulture) : -1);
}
set {
Attributes["rows"] = MapIntegerAttributeToString(value);
}
}
/// <devdoc>
/// <para>Gets or sets the content of the text area.</para>
/// </devdoc>
[
WebCategory("Appearance"),
DefaultValue(""),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
]
public string Value {
get {
return InnerText;
}
set {
InnerText = value;
}
}
/// <devdoc>
/// <para>Occurs when the content of the <see langword='HtmlTextArea'/> control is changed upon server
/// postback.</para>
/// </devdoc>
[
WebCategory("Action"),
WebSysDescription(SR.HtmlTextArea_OnServerChange)
]
public event EventHandler ServerChange {
add {
Events.AddHandler(EventServerChange, value);
}
remove {
Events.RemoveHandler(EventServerChange, value);
}
}
/// <internalonly/>
/// <devdoc>
/// Overridden to only allow literal controls to be added as Text property.
/// </devdoc>
protected override void AddParsedSubObject(object obj) {
if (obj is LiteralControl || obj is DataBoundLiteralControl)
base.AddParsedSubObject(obj);
else
throw new HttpException(SR.GetString(SR.Cannot_Have_Children_Of_Type, "HtmlTextArea", obj.GetType().Name.ToString(CultureInfo.InvariantCulture)));
}
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected override void RenderAttributes(HtmlTextWriter writer) {
if (Page != null) {
Page.ClientScript.RegisterForEventValidation(RenderedNameAttribute);
}
writer.WriteAttribute("name", RenderedNameAttribute);
Attributes.Remove("name");
base.RenderAttributes(writer);
}
/// <devdoc>
/// <para>Raised the <see langword='ServerChange'/>
/// event.</para>
/// </devdoc>
protected virtual void OnServerChange(EventArgs e) {
EventHandler handler = (EventHandler)Events[EventServerChange];
if (handler != null) handler(this, e);
}
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected internal override void OnPreRender(EventArgs e) {
base.OnPreRender(e);
if (!Disabled) {
// if no change handler, no need to save posted property
if (Events[EventServerChange] == null) {
ViewState.SetItemDirty("value",false);
}
if (Page != null) {
Page.RegisterEnabledControl(this);
}
}
}
/*
* Method of IPostBackDataHandler interface to process posted data.
* TextArea process a newly posted value.
*/
/// <internalonly/>
/// <devdoc>
/// </devdoc>
bool IPostBackDataHandler.LoadPostData(string postDataKey, NameValueCollection postCollection) {
return LoadPostData(postDataKey, postCollection);
}
protected virtual bool LoadPostData(string postDataKey, NameValueCollection postCollection) {
string current = Value;
string text = postCollection.GetValues(postDataKey)[0];
if (current == null || !current.Equals(text)) {
ValidateEvent(postDataKey);
Value = text;
return true;
}
return false;
}
/*
* Method of IPostBackDataHandler interface which is invoked whenever posted data
* for a control has changed. TextArea fires an OnServerChange event.
*/
/// <internalonly/>
/// <devdoc>
/// </devdoc>
void IPostBackDataHandler.RaisePostDataChangedEvent() {
RaisePostDataChangedEvent();
}
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected virtual void RaisePostDataChangedEvent() {
OnServerChange(EventArgs.Empty);
}
}
}
|