//写cookies函数

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

{

    var Days = 30; //此 cookie 将被保存 30 天

    var exp = new Date();    //new Date("December 31, 9998");

    exp.setTime(exp.getTime() + Days * 24 * 60 * 60 * 1000);

    document.cookie = name + "=" + escape(value) + ";expires=" + exp.toGMTString();

}

function getCookie(name)//取cookies函数

{

    var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));

    if (arr != null) return unescape(arr[2]); return null;

}

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();

}