ajax提交

$.ajax({
                url: "{:U('/admin/User/checkloginajax')}",
                type: "post",
                dataType: "json",
                data: {
                    username: username,
                    password: password,
                    vcode: vcode

                }
            }).done(function (g) {
                if (g.status == 1) {
                    window.location.href = "{:U('/admin/Index/index')}";
                } else {
                    alert(g.info);
                    $('#vcode').attr("src", verifyimg.replace(/\?.*$/, '') + '?' + Math.random());
                }

            })