ASP.NET Ajax用户名注册验证

 

ASP.NET Ajax用户名注册验证

<asp:TextBox ID="txtUserName" runat="server" onBlur="send_request('addAdmin');"></asp:TextBox>

//script处理函数

      <script language="javascript" type="text/javascript">

          function send_request(flag)

          {

              //创建XMLHttpRequest;

              http_request = false;

              if(window.XMLHttpRequest)

              {

                  //　非IE　浏览器

                  http_request = new XMLHttpRequest();

              }

              else if(window.ActiveXObject)

              {

                  //IE

                  try

                  {

                      http_request = new ActiveXObject("Msxml2.XMLHTTP");//较新版本的IE

                  }catch(e)

                  {

                      try

                      {

                          http_request = new ActiveXOBject("Microsoft.XMLHTTP");//旧版本IE

                      }catch(e){}                    

                  }

              }

              else

              {

                  window.alert("不能创建　XMLHttpRequest对象，无法应用Ajax");

                  return false;

              }

              //指定回调函数

              if(flag == "addAdmin")

              {

                   http_request.onreadystatechange = addAdmin;

                    //创建HTTP请求

                   http_request.open("get","Handler.ashx?flag=addAdmin&userName="+document.getElementById("txtUserName").value,true);

            

              }

               else if(flag == "updateTitle")

               {

                  http_request.onreadystatechange = updateTitle;

                   //创建HTTP请求

                   i = document.getElementById("ddlVoteTitle").selectedIndex;//选择的索引

                   id = document.form1.ddlVoteTitle.options[i].value;

                   http_request.open("get","Handler.ashx?flag=updateTitle&id="+id,true);

            

               }

           

           

              //发送上面创建的HTTP请求

              http_request.send(null);  

          }

          function addAdmin()

          {  

              if(http_request.readyState == 4)//发送成功

              {

                  if(http_request.status == 200)//交易成功

                  {

                      //正式处理有信息

                      if(http_request.responseText == "该用户已经存在")

                      {

                          //隐藏提交按扭

                          document.getElementById("Button1").style.display ="none";

                      }

                      else

                      {

                          document.getElementById("Button1").style.display="";

                      }

                   

                      document.getElementById("lblShow").innerText=http_request.responseText;

                  }

              }

          }

          function updateTitle()

          {

              if(http_request.readyState == 4)//发送成功

              {

                  if(http_request.status == 200)//交易成功

                  {

                      //正式处理有信息

                   

                      document.getElementById("lblTitle").innerText=http_request.responseText;

                  }

              }

          }

      </script>

//创建一般处理程序

//Handler.ashx

<%@ WebHandler Language="C#" Class="Handler" %>

using System;

using System.Web;

public class Handler : IHttpHandler {

      DB DBManager = new DB();

        

      public void ProcessRequest (HttpContext context) {

          context.Response.ContentType = "text/plain";

        

          string flag = context.Request.QueryString["flag"].ToString();

          if (flag.Equals("addAdmin"))

          {

              string userName = context.Request.QueryString["userName"].ToString();

              string strSql = "select count(*) from admin where userName = '" + userName + "'";

              if (Convert.ToInt32(DBManager.executeGetReturn(strSql)) > 0)

              {

                  context.Response.Write("该用户已经存在");

              }

              else

              {

                  context.Response.Write("你可以注册［" + userName + "］");

              }

          }

          else if (flag.Equals("updateTitle"))

          {

              int id = Convert.ToInt32(context.Request.QueryString["id"].ToString());

              string strSql = "update voteConfig set id=" + id;

              if (DBManager.executeNonQuery(strSql) > 0)

              {

                  context.Response.Write("设置已成功，当前系统前调查［" + DBManager.executeGetReturn("select voteTitle from voteMaster where id=" + id) + "］");

              }

              else

              {

                  context.Response.Write("设置失败");

              }

          }

      }

      public bool IsReusable {

          get {

              return false;

          }

      }

}