所以在后台通过Request.Form来获取所要的数据，test.aspx.cs代码如下
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace ExampleTest
{
public partial class test : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
String key = Request.Form["__EVENTTARGET"];
if (!String.IsNullOrWhiteSpace(key))
{
String value = Request.Form["__EVENTARGUMENT"];
String info = "Key=" + key + " Value=" + value;
Response.Write("<script type=\"text/javascript\">alert('" + info + "');</script>");
TextBox1.Text = info;
}
}
}
}
注：
对于Button和ImageButton会有不一样，可以参考下面的文章
http://blog.csdn.net/luxuejuncarl/article/details/1479226
http://www.cnblogs.com/hjf1223/archive/2006/07/05/443761.html
附前端代码
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="test.aspx.cs" Inherits="ExampleTest.test" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title></title>
<script type="text/javascript">
function test() {
__doPostBack("AA", "111");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<input id="btnTest" type="button" onclick="test();" value="test" />
<asp:TextBox ID="TextBox1" runat="server" AutoPostBack="true"></asp:TextBox>
</div>
</form>
</body>
</html>
ASP.NET之通过JS向服务端(后台)发出请求(__doPostBack is undefined),布布扣,bubuko.com
ASP.NET之通过JS向服务端(后台)发出请求(__doPostBack is undefined)
原文：http://blog.csdn.net/xxdddail/article/details/27096583