js中cookie的使用

//注意。。。要启动服务器才能启用cookie
function SetCookie(name, value)
{
    var expdate = new Date();
    var argv = SetCookie.arguments;
    var argc = SetCookie.arguments.length;
    var expires = (argc > 2) ? argv[2] : null;
    //alert("expires:"+expires);
    var path = (argc > 3) ? argv[3] : null;
    //alert("path:"+path);
    var domain = (argc > 4) ? argv[4] : null;
    //alert("domain:"+domain);
    var secure = (argc > 5) ? argv[5] : false;
    //alert("secure:"+secure);
    //设置cookie有效期为60*30天，可以自行更改或者将过期时间设为参数
    expdate.setTime(expdate.getTime() + ( 60 * 30 * 24 * 60 * 60 * 1000 ));
    document.cookie = name + "=" + escape (value) + "; expires="+ expdate.toGMTString()
    +((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain))
    +((secure == true) ? "; secure" : "");
}
//==========================================================
//2.    读取Cookie
function GetCookie(name)
{
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen)
    {
    var j = i + alen;
    if (document.cookie.substring(i, j) == arg)
    return GetCookieVal (j);
    i = document.cookie.indexOf(" ", i) + 1;
    if (i == 0) break;
    }
    return "";
}
//==========================================================
//3.    删除Cookie
function DelCookie(name)
{
    var exp = new Date();
    exp.setTime (exp.getTime() - 1);
    var cval = GetCookie (name);
    document.cookie = name + "=" + cval + "; expires="+ exp.toGMTString();
}