<script language="JavaScript" type="text/javascript">
<!--
var Cookie=new Object();

Cookie.setCookie=function(name,value,option){
 //用于存储赋值给document.cookie的cookie格式字符串
 var str=name+"="+escape(value);  
 if(option){
  //如果设置了过期时间
  if(option.expireDays){
   var date=new Date();
   var ms=option.expireDays*24*3600*1000;
   date.setTime(date.getTime()+ms);
   str+="; expires="+date.toGMTString();
  } 
  if(option.path)str+="; path="+path;   //设置访问路径
  if(option.domain)str+="; domain"+domain; //设置访问主机
  if(option.secure)str+="; true";    //设置安全性
 }
 document.cookie=str;
}

Cookie.getCookie=function(name){
 var cookieArray=document.cookie.split("; "); //得到分割的cookie名值对
 var cookie=new Object();
 for(var i=0;i<cookieArray.length;i++){
  var arr=cookieArray[i].split("=");    //将名和值分开
  if(arr[0]==name)return unescape(arr[1]); //如果是指定的cookie，则返回它的值
 }
 return "";
}

Cookie.deleteCookie=function(name){
 this.setCookie(name,"",{expireDays:-1}); //将过期时间设置为过去来删除一个cookie
}

Cookie.setCookie("user","jack");
alert(Cookie.getCookie("user"));
Cookie.deleteCookie("user");
alert(Cookie.getCookie("user"));


//-->
</script>

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