ASP.NET AJAX无刷新验证用户名

  极其简单,自行扩展
  HTML代码
  <%@ Page Language=”C#” AutoEventWireup=”true” CodeFile=”Default.aspx.cs” Inherits=”_Default” %>
  <!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.1//EN” “http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd“>
  <html xmlns=”http://www.w3.org/1999/xhtml“>
  <head runat=”server”>
   <title>Untitled Page</title>
   <script type=”text/javascript”>
   function GetUser()
  {
   requestSimpleService = WebServiceSample.GetUser(document.getElementById(’UserName’).value, OnRequestComplete);
   return false;
  }
  //显示提示信息
  function OnRequestComplete(result)
  {
   if(result == ‘true’)
   {
   document.getElementById(’Message’).innerHTML = ‘提示:用户名已被注册.’;
   document.getElementById(’PostButton’).disabled = ‘disabled’;
   }
   else
   {
   document.getElementById(’Message’).innerHTML = ‘提示:用户名可以使用.’;
   document.getElementById(’PostButton’).disabled = ”;
   }
  }
   </script>
  </head>
  <body>
   <form id=”form1″ runat=”server”>
   <asp:ScriptManager ID=”ScriptManager1″ runat=”server”>
   <Services>
   <asp:ServiceReference Path=”WebServiceSample.asmx” />
   </Services>
   </asp:ScriptManager>
   <input id=”UserName” type=”text” onblur=”return GetUser()” />
  <input id=”PostButton” type=”button” value=”注 册” disabled=”disabled” /><br />
   <div id=”Message”></div>
   </form>
  </body>
  </html>
  WebService代码
  using System;
  using System.Web;
  using System.Collections;
  using System.Web.Services;
  using System.Web.Services.Protocols;
  using System.Web.Script.Services;
  /// <summary>
  /// WebServiceSample 的摘要说明
  /// </summary>
  [WebService(Namespace = "http://tempuri.org/")]
  [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
  [ScriptService]
  public class WebServiceSample : System.Web.Services.WebService
  {
   public WebServiceSample () {
   //如果使用设计的组件,请取消注释以下行
   //InitializeComponent();
   }
   [WebMethod]
   public string GetUser(string strUser)
   {
   string strMessage = null;
   if (strUser == “ADMIN”)
   {
   strMessage = “true”;
   }
   else
   {
   strMessage = “false”;
   }
   return strMessage;
   }
  }