对“添加”、“提交”、“保存”、“更新”等按钮需要对数据库进行写操作的按钮，一定要在页面初始化时加载脚本，防止多次重复点击，例如：
protected void Page_Load(object sender, EventArgs e)
{
//.net1.1
Button1.Attributes.Add("onclick", "this.disabled=true;" + this.GetPostBackEventReference(this.Button1));
//.net 2.0以上
Button1.Attributes.Add("onclick", "this.disabled=true;" + this.ClientScript.GetPostBackEventReference(Button1, ""));
}
为了测试，我们可以建立一个页面，加入一个btnAdd按钮
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="AddAndEditUser.aspx.cs" Inherits="AddUser" %><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>添加和编辑页面示例</title>
</head>
<body>
<form id="frmMain" runat="server">
<asp:Button ID="btnAdd" runat="server" CssClass="INPUT-BUTTON-Save" OnClick="btnAdd_Click">
</asp:Button>
</form>
</body>
</html>
/*----------------------------------------------------------------
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
public partial class AddUser : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
btnAdd.Attributes.Add("onclick", "this.disabled=true;" + this.ClientScript.GetPostBackEventReference(btnAdd, ""));
}
protected void btnAdd_Click(object sender, EventArgs e)
{
//模拟网络拥塞5秒钟
System.Threading.Thread.Sleep(5000);
}
}
可见当点击了按钮，需要等5秒钟按钮才能点击。即页面回发一后按钮才能用。这样可以有效的防止用户多次点击按钮，造成多次提交！