var   http_request = false;   
  	function   send_request(url)
	{  //初始化、指定处理函数、发送请求的函数   
  		http_request   =   false;  //开始初始化XMLHttpRequest   对象   		   
  		if(window.XMLHttpRequest)
		{ //Mozilla   浏览器   
 		 	http_request   =   new   XMLHttpRequest();   
 		    if (http_request.overrideMimeType)
			{//设置MiME   类别   
 			    http_request.overrideMimeType("text/xml");   
 		 	}   
 		 }  
  		else if (window.ActiveXObject)
		{   //   IE   浏览器   
  			try {   
  				http_request = new ActiveXObject("Msxml2.XMLHTTP");   
  			} catch (e) {   
  				try {   
  					http_request   =   new   ActiveXObject("Microsoft.XMLHTTP");   
  				} catch (e) {}   
  			}   
		}   
  		if (!http_request) {   //   异常，创建对象实例失败   
  			window.alert("不能创建XMLHttpRequest   对象实例.");   
  			return   false;   
  		}   
  		http_request.onreadystatechange   =   processRequestyzm;   
  		//   确定发送请求的方式和URL   以及是否同步执行下段代码   
  		http_request.open("GET",   url,   true);   
  		http_request.send(null);   
  	}   
       
  	function  processRequestyzm()  //   处理返回信息的函数 
  	{   
		if   (http_request.readyState   ==   4)  
		{   //   判断对象状态   
  			if   (http_request.status   ==   200)   
			{   //   信息已经成功返回，开始处理信息			
				//alert(http_request.responseText);
				if(http_request.responseText != 1){				
					document.getElementById("showcheckyzm").innerHTML = "验证码输入错误";	
					document.getElementById("yzmtt").value = "no";	
					document.getElementById("txtyzm").value = "";	
				}else{
					document.getElementById("showcheckyzm").innerHTML = "";	
					document.getElementById("yzmtt").value = "yes";	
				}		 
  			}   else   {   //页面不正常   
  				alert("您所请求的页面有异常。");   
  			}   
  		}   
  	} 
    function  checkyzm()   //发送请求的函数
	{   
  		//var   ff   =   document.form1;   
  		var   sendyzm   =   document.form1.txtyzm.value;   
  		if(sendyzm!="")   { 		 
  			send_request('../js/yzmcheck.jsp?svalue='+sendyzm); 
  			//document.getElementById("showcheckyzm").innerHTML = "系统正在验证...";  
  		}   
  	}