javascript设置和获取cookie的通用方法

//写cookies
function setCookie(name,value) {
    var Days = 30;
    var exp = new Date();
    exp.setTime(exp.getTime() + Days*24*60*60*1000);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
}

//读取cookies
function getCookie(name) {
    var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");

if(arr=document.cookie.match(reg)){
    return unescape(arr[2]);
} else{
      return null;
}

}

//删除cookies
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();
}

}
//使用示例
setCookie("name","hayden");
alert(getCookie("name"));
</script>