//获得Cookie解码后的值
function GetCookieVal(offset) {
	var endstr = document.cookie.indexOf(";", offset);
	if (endstr == -1)
		endstr = document.cookie.length;
	return unescape(document.cookie.substring(offset, endstr));
}

//设定Cookie值
function SetCookie(name, value) {
	var expdate = new Date();
	var argv = SetCookie.arguments;
	var argc = SetCookie.arguments.length;
	var expires = (argc > 2) ? argv[2] : null;
	var path = (argc > 3) ? argv[3] : null;
	var domain = (argc > 4) ? argv[4] : null;
	var secure = (argc > 5) ? argv[5] : false;
	if (expires != null)
		expdate.setTime(expdate.getTime() + (expires * 24 * 60 * 60 * 1000));
	document.cookie = name + "=" + escape(value)
			+ ((expires == null) ? "" : ("; expires=" + expdate.toGMTString()))
			+ ((path == null) ? "" : ("; path=" + path))
			+ ((domain == null) ? "" : ("; domain=" + domain))
			+ ((secure == true) ? "; secure" : "");
}

//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();
}

//获得Cookie的原始值
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 null;
}