function SetCookieFun(name, value)//两个参数，一个是cookie的名子，一个是值！ 存入cookie

{
    var exp = new Date();    //new Date("December 31, 9998");  保存30分钟
    exp.setTime(exp.getTime() + 30 * 60 * 1000);
    document.cookie = name + "=" + escape(value) + ";expires=" + exp.toGMTString();
}
function getCookieFun(name)
 {
    var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));
    if (arr != null) return unescape(arr[2]); return null;
}
//清空所有的cookie
function clearAllCookie() {
    var keys = document.cookie.match(/[^ =;]+(?=\=)/g);
    if (keys) {
        for (var i = keys.length; i--;)
            document.cookie = keys[i] + ‘=0;expires=‘ + new Date(0).toUTCString()
    }



}