function CookieClass()
{
    this.expires = 0 ; //有效时间,以分钟为单位
    this.path = ""; //设置访问路径
    this.domain = ""; //设置访问主机
    this.secure = false; //设置安全性
    
    this.setCookie = function(name,value)
    {
        var str = name+"="+escape(value);
        if (this.expires>0) //如果设置了过期时间
        {
            var date=new Date();
            var ms=this.expires * 60 * 1000; //每分钟有60秒，每秒1000毫秒
            date.setTime(date.getTime()+ms);
            str+="; expires="+date.toGMTString();
        }
        if(this.path!="")str+="; path="+this.path; //设置访问路径
        if(this.domain!="")str+="; domain="+this.domain; //设置访问主机
        if(this.secure!="")str+="; true"; //设置安全性
            
        var value=this.getCookie(name);
        if(value!=""||value!=null) this.deleteCookie(name);
        document.cookie=str;
    }

    this.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 "";
    }

    this.deleteCookie=function(name)
    {
        var date=new Date();
        var ms= 1 * 1000;
        date.setTime(date.getTime() - ms);
        var str = name+"=no; expires=" + date.toGMTString(); //将过期时间设置为过去来删除一个cookie
        document.cookie=str;
    }

    this.showCookie=function()
    {
       // alert(unescape(document.cookie));
    }
}
    
var cook = new CookieClass();
cook.expires =1;//一分钟有效


//获取cookie
    function getCookie(objName,keyName)
  {
    var result = "";
    //如果Cookie长度大于0
    if(document.cookie.length > 0)
    {
        //包含多个cookie的数组
        var objArray = document.cookie.split(";");
        //Cookie对象名
        var objSearch = objName + "=";
        //Cookie键名称
        var nameSearch = keyName + "=";
        for(var i=0;i<objArray.length;i++)
        {
            //如果数组中(cookie)包含对象名
            if (objArray[i].indexOf(objSearch) != -1)
            {
                //在数组中取Cookie值
                begin = objArray[i].indexOf(nameSearch);
                if(begin != -1)
                {
                    begin += nameSearch.length;
                    end = objArray[i].indexOf("&",begin);
                    if(end == -1)
                    {
                        end = objArray[i].length;
                    }
                    result = decodeURI(objArray[i].substring(begin, end));
                }
            }
        }
     }
   return result;
 }

//删除cookie
function delCookie(name)//删除cookie
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}