广告验证码的实现

1、js 代码 

 

<script type="text/javascript">

 jr_vids="verifyCode";

 jrdomains=["www.shurumedia.com","www.shurumedia.cn"]; jr_vd=4;

 jr_a_client="85"; jr_a_zones="50";jrdomain=jrdomains[parseInt(Math.random()*jrdomains.length)];

 (function(){

 	var w=window,d=document,timeid=null,wtop=w.top,index=0,fdm=jrdomain;

 	wtop.jrdomains=jrdomains;

 	if(!wtop.jrvcodeids)wtop.jrvcodeids=[];

	for(var i=0,ids=jr_vids.split(','); i<ids.length; i=i+1){wtop.jrvcodeids.push({id:ids[i],zoneid:jr_a_zones,uid:jr_a_client});}

	function loadjs(url){var h=d.getElementsByTagName("head")[0];var sc=d.createElement("script");sc.src=url;sc.charset="GBK";h.appendChild(sc);}

 	function init(old){

 		var url='http://' + jrdomain+'/js/cpynew.js?old='+old;loadjs(url);

		wtop.jrdomain=jrdomain;if(timeid){clearTimeout(timeid);timeid=null;}

 		setTimeout(function(){

 			if(!wtop.jradsloaded){ 			

 				for(var i=index; i<jrdomains.length;i++){if(jrdomains[i]!=fdm&&jrdomains[i]!=jrdomain){jrdomain=jrdomains[i];index++;init(url);break;}}	

 			}

 		}, 3000); 		

 	}if(!wtop.jradsloaded)init(); //won

 })(); 

</script>

 

 

2. html  代码

 

                    验证码：<input type="text" name="verifyCode" id="verifyCode" />

 

将此代码放入form表单，在提交时回自动去校验验证码的正确性