ajax之用户注册检测代码版

var objRequest;
function getajax()
{
try
{
   objRequest = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e)
{
  try
     {
     objRequest = new ActiveXObject("Microsoft.XMLHTTP");
     }
  catch(oc)
   {
     objRequest=null;
   }
}
}
//以上为公共部分
function Isname() //函数名，自定义
{ getajax();
  var name = document.getElementById("name").value;
if(!objRequest&&typeof XMLHttpRequest!="undefined")
   {objRequest=new XMLHttpRequest();}
var url="ajax.asp?action=Isreg&name="+escape(name);
   if(objRequest!=null)
     {
       objRequest.onreadystatechange = nameProcess;
       objRequest.open("GET",url,true);
       objRequest.send(null);
     }
}
  
function nameProcess()
{
var objname = document.getElementById("nametest");

  if(objRequest.readyState<4){
objname.innerHTML="正在检测";
  }
  else if(objRequest.readyState == 4){
   var response = objRequest.responseText;
objname.innerHTML=unescape(response);
  }
   else{
objname.innerHTML = "Error:"+objRequest.statusText;
  }
     //此处else可不要
}

<!--#include file="conn.asp"-->
<%if Request.QueryString("action")="Isreg" then
name=Request.QueryString("name")
'以上为ajax.js的两个传递
namelng=len(name)
if namelng<4 or namelng>20 then
response.write "<font color=#ff0000>用户名长度不符。</font>"
else
  set Isins=conn.Execute("select [name] from [user] where [name]='"&name&"'")
     if (Isins.bof and Isins.eof) then
     response.write "可以注册"
     else
     response.write "<font color=#ff0000>已被注册</font>"
        end if
     end if
   set Isins=nothing
  end if%>

<script type="text/javascript" src="include/ajax.js"/></script>
     用户名：<input name="name" type="text" id="name" size="16" maxlength="16" onChange="Isname();"><span id="nametest"></span>