javascript操作cookie

//写cookies函数
function setCookie(name,value)//两个参数,一个是cookie的名子,一个是值
{
    if(getCookie(name)!=null)delCookie(name);
    var Hour = 3; //此 cookie 将被保存 3 小时
    var exp  = new Date();    //new Date("December 31, 9998");
    exp.setTime(exp.getTime() + Hour*60*60*1000);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
}
 
//取cookies函数
function getCookie(name)       
{
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
     if(arr != null) return unescape(arr[2]); return null;
}
 
//删除cookie
function delCookie(name)
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}