前台代码：
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>无标题页</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="username" runat="server"></asp:TextBox><asp:Label ID="Label2" runat="server"
></asp:Label>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
后台代码：
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 Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
ScriptManager1.RegisterAsyncPostBackControl(Button1);
}
protected void Button1_Click(object sender, EventArgs e)
{
try
{
if (username.Text == "")
{
this.Label2.Text = "请输入昵称！";
return;
}
}
catch (Exception ee)
{
ScriptManager.RegisterStartupScript(this.UpdatePanel1, this.GetType(), "Button1_Click", "<script>alert('" + ee.Message + "')</script>", true);
}
}
}
错误提示："Sys.WebForms.PageRequestManagerServerErrorException: 在服务器上处理请求时出现未知错误。服务器返回的状态码为: 12030"
