js操作cookie

function set_cookie(key, value, exp, path, domain, secure) {
        path = "/";
        var cookie_string = key + "=" + escape(value);
        if (exp) {
            cookie_string += "; expires=" + exp.toGMTString();
        }
        if (path)
            cookie_string += "; path=" + escape(path);
        if (domain)
            cookie_string += "; domain=" + escape(domain);
        if (secure)
            cookie_string += "; secure";
        document.cookie = cookie_string;
    }

    /*读取 cookie*/
    function get_cookie(cookie_name) {
        var results = document.cookie.match('(^|;) ?' + cookie_name + '=([^;]*)(;|$)');
        if (results)
            return (unescape(results[2]));
        else
            return null;
    }

    /*删除 cookie*/
    function del_cookie(cookie_name) {
        var cookie_date = new Date();
        //current date & time
        cookie_date.setTime(cookie_date.getTime() - 1);
        document.cookie = cookie_name += "=; expires=" + cookie_date.toGMTString();
    }