【转】打造防止重复提交按钮

protected override void AddAttributesToRender(HtmlTextWriter writer)
{
System.Text.StringBuilder ClientSideEventReference = new System.Text.StringBuilder();

if (((this.Page != null) && this.CausesValidation) && (this.Page.Validators.Count > 0))
{
ClientSideEventReference.Append("if (typeof(Page_ClientValidate) == 'function'){if (Page_ClientValidate() == false){return false;}}");
}
//ShowMessageBox?
if (this.ShowMessageBox)
{
ClientSideEventReference.Append("if (!confirm('" + this.WarningText + "')){return false}");
}
ClientSideEventReference.AppendFormat("this.value = '{0}';", (string)this.ViewState["afterSubmitText"]);
ClientSideEventReference.Append("this.disabled = true;");
ClientSideEventReference.Append(this.Page.ClientScript.GetPostBackEventReference(this, string.Empty));

writer.AddAttribute(HtmlTextWriterAttribute.Onclick, ClientSideEventReference.ToString(), true);
base.AddAttributesToRender(writer);
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace BlogLan.Web.Controls
{
/// <summary>
/// 表示一个防止重复提交的按钮。当用户单击按钮以后，该按钮变灰，不能再次单击，直到重新加载页面或者跳转。
/// </summary>
[DefaultProperty("Text")]
[ToolboxData("<{0}:ClickOnceButton runat=server></{0}:ClickOnceButton>")]
public class ClickOnceButton : System.Web.UI.WebControls.Button
{
/// <summary>
/// 默认的构造函数。
/// </summary>
public ClickOnceButton()
{
this.ViewState["afterSubmitText"] = "正在提交，请稍候...";
base.Text = "ClickOnceButton";
this.ViewState["showMessageBox"] = false;
this.ViewState["warningText"] = "确定要提交吗？";
}

/// <summary>
/// 获取或设置单击按钮后，按钮上所显示的文本。
/// </summary>
[Bindable(true),
Category("Appearance"),
DefaultValue("正在提交，请稍候..."),
Description("指示单击提交后，按钮上所显示的文本。")]
public string AfterSubmitText
{
get
{
string afterSubmitText = (string)this.ViewState["afterSubmitText"];
if (afterSubmitText != null)
{
return afterSubmitText;
}
else
{
return string.Empty;
}
}
set
{
this.ViewState["afterSubmitText"] = value;
}
}

[Bindable(true),
Category("Appearance"),
DefaultValue(false),
Description("指示是否要显示一个提示框。")]
public bool ShowMessageBox
{
get
{
return (bool)this.ViewState["showMessageBox"];
}
set
{
this.ViewState["showMessageBox"] = value;
}
}

[Bindable(true),
Category("Appearance"),
DefaultValue("确定要提交吗？"),
Description("指示提示框内所包含的内容。")]
public string WarningText
{
get
{
return (string)this.ViewState["warningText"];
}
set
{
this.ViewState["warningText"] = value;
}
}

/// <summary>
/// AddAttributesToRender
/// </summary>
/// <param name="writer">HtmlTextWriter</param>
protected override void AddAttributesToRender(HtmlTextWriter writer)
{
System.Text.StringBuilder ClientSideEventReference = new System.Text.StringBuilder();

if (((this.Page != null) && this.CausesValidation) && (this.Page.Validators.Count > 0))
{
ClientSideEventReference.Append("if (typeof(Page_ClientValidate) == 'function'){if (Page_ClientValidate() == false){return false;}}");
}
//ShowMessageBox?
if (this.ShowMessageBox)
{
ClientSideEventReference.Append("if (!confirm('" + this.WarningText + "')){return false}");
}
ClientSideEventReference.AppendFormat("this.value = '{0}';", (string)this.ViewState["afterSubmitText"]);
ClientSideEventReference.Append("this.disabled = true;");
ClientSideEventReference.Append(this.Page.ClientScript.GetPostBackEventReference(this, string.Empty));

writer.AddAttribute(HtmlTextWriterAttribute.Onclick, ClientSideEventReference.ToString(), true);
base.AddAttributesToRender(writer);
}
}
}