几个错误的思考，不知道是否正确。

 public static async Task<HttpResponse<T>> HttpPostTaskAsync<T>(string url, object q)
        {
            try
            {
                StringContent content = new StringContent(JsonConvert.SerializeObject(q, new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore }));
                content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
                var ret = await _HC.PostAsync(url, content);
                if (!ret.IsSuccessStatusCode)//Api相关错误，重试无效，理论上应该在开发阶段全部排除
                    return new HttpResponse<T>(false, ret.ReasonPhrase);
                var msg = await ret.Content.ReadAsStringAsync();
                return new HttpResponse<T>(true, msg);

            }
            catch (HttpRequestException ex)//网络错误，可以重试
            {
                throw;

            }
            catch (System.Exception ex) //其他错误，马上修改
            {
                throw;

            }
        }

[C#] HttpClient的一点思考