public async Task <IActionResult> Index()
        {
            var token      = _weixinAccessToken.GetToken();
            var resultJson = await MenuApi.GetMenuAsync(token);

            var vm = new WeixinJsonViewModel
            {
                Token = token,
                Json  = JsonConvert.SerializeObject(resultJson, Formatting.Indented)
            };

            return(View(vm));
        }