public IActionResult OnPost()
        {
            var res = _grpcSrv.MethodInvoke(Endpoint, MethodName, RequestJson);

            return(new JsonResult(new { respJson = res }));
        }
        public async Task <IActionResult> OnPost()
        {
            var res = await _grpcSrv.MethodInvoke(Endpoint, MethodName, RequestJson);

            return(new JsonResult(new { respJson = res }));
        }