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//------------------------------------------------------------------------------
// <copyright file="HtmlButton.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
/*
* HtmlButton.cs
*
* Copyright (c) 2000 Microsoft Corporation
*/
namespace System.Web.UI.HtmlControls {
using System.ComponentModel;
using System;
using System.Collections;
using System.Web;
using System.Web.UI;
using System.Security.Permissions;
/// <devdoc>
/// <para>The <see langword='HtmlButton'/>
/// class defines the methods, properties and events for the
/// <see langword='HtmlButton'/>
/// control. This
/// class allows programmatic access to the HTML <button> element
/// on the server.</para>
/// </devdoc>
[
DefaultEvent("ServerClick"),
SupportsEventValidation,
]
public class HtmlButton : HtmlContainerControl, IPostBackEventHandler {
private static readonly object EventServerClick = new object();
/*
* Creates an intrinsic Html BUTTON control.
*/
/// <devdoc>
/// <para>Initializes a new instance of a <see cref='System.Web.UI.HtmlControls.HtmlButton'/> class.</para>
/// </devdoc>
public HtmlButton() : base("button") {
}
/// <devdoc>
/// <para>Gets or sets whether pressing the button causes page validation to fire. This defaults to True so that when
/// using validation controls, the validation state of all controls are updated when the button is clicked, both
/// on the client and the server. Setting this to False is useful when defining a cancel or reset button on a page
/// that has validators.</para>
/// </devdoc>
[
WebCategory("Behavior"),
DefaultValue(true),
]
public virtual bool CausesValidation {
get {
object b = ViewState["CausesValidation"];
return((b == null) ? true : (bool)b);
}
set {
ViewState["CausesValidation"] = value;
}
}
[
WebCategory("Behavior"),
DefaultValue(""),
WebSysDescription(SR.PostBackControl_ValidationGroup)
]
public virtual string ValidationGroup {
get {
string s = (string)ViewState["ValidationGroup"];
return((s == null) ? String.Empty : s);
}
set {
ViewState["ValidationGroup"] = value;
}
}
/// <devdoc>
/// <para>Occurs when the user clicks an <see cref='System.Web.UI.HtmlControls.HtmlButton'/> control on the
/// browser.</para>
/// </devdoc>
[
WebCategory("Action"),
WebSysDescription(SR.HtmlControl_OnServerClick)
]
public event EventHandler ServerClick {
add {
Events.AddHandler(EventServerClick, value);
}
remove {
Events.RemoveHandler(EventServerClick, value);
}
}
/// <internalonly/>
protected internal override void OnPreRender(EventArgs e) {
base.OnPreRender(e);
if (Page != null && Events[EventServerClick] != null)
Page.RegisterPostBackScript();
}
/*
* Override to generate postback code for onclick.
*/
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected override void RenderAttributes(HtmlTextWriter writer) {
bool submitsProgramatically = (Events[EventServerClick] != null);
if (Page != null && submitsProgramatically) {
Util.WriteOnClickAttribute(
writer, this, false, true,
(CausesValidation && Page.GetValidators(ValidationGroup).Count > 0),
ValidationGroup);
}
base.RenderAttributes(writer);
}
/// <devdoc>
/// <para>Raises the <see langword='ServerClick'/>
/// event.</para>
/// </devdoc>
protected virtual void OnServerClick(EventArgs e) {
EventHandler handler = (EventHandler)Events[EventServerClick];
if (handler != null) handler(this, e);
}
/*
* Method of IPostBackDataHandler interface to raise events on post back.
* Button fires an OnServerClick event.
*/
/// <internalonly/>
/// <devdoc>
/// </devdoc>
void IPostBackEventHandler.RaisePostBackEvent(string eventArgument) {
RaisePostBackEvent(eventArgument);
}
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected virtual void RaisePostBackEvent(string eventArgument) {
ValidateEvent(UniqueID, eventArgument);
if (CausesValidation) {
Page.Validate(ValidationGroup);
}
OnServerClick(EventArgs.Empty);
}
}
}
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