HttpClient 的 PostAsync 方法在 2-3 个超时请求后抛出聚合异常

Question

I am making a webrequest using HttpClient and it involves "Timeout" feature, everything works fine apart from the timeout feature

which throws an "Aggregate Exception" when a request is hit 2-3 times(like click on Sign In button and request gets timed out).

i ve tried "Catching" the exception but it doesnt work.

Code used :

        try
        {
            HttpClient httpClient = new HttpClient();

           //explicit timeout for testing

           TimeSpan requestTimeout = new TimeSpan(1000);
            httpClient.Timeout = requestTimeout;
            HttpContent httpContent = new StringContent(postJSON);
            httpContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");
            HttpResponseMessage response = null;

            response = await httpClient.PostAsync(url, httpContent);
            if (response != null)
            {
                response.EnsureSuccessStatusCode();
                netResults = await response.Content.ReadAsStringAsync();
                Logger.Log("NetworkRequest:ResponseStream:Json result:" + netResults);
            }

            if (this.convertedType != null)
            {
                MemoryStream assetReader = GetMemoryStreamFromString(netResults);
                assetReader.Position = 0;
                object value = fromJSON(assetReader, this.convertedType);
                networkReqSuccessWithObjectCallback(this, value);
            }
            else
            {
                //Return netResult as string.
                networkReqSuccessWithStringCallback(this, netResults);
            }
        }

        catch (TaskCanceledException)
        {
            ErrorException ee = null;
            ee = new ErrorException("RequestTimeOut");
            NotifyNetworkDelegates(ee);
        }

        catch (WebException we)
        {
            // failure
            ErrorException ee = null;
            ee = ErrorException.fromJSON(we.Message);
            NotifyNetworkDelegates(ee);
        }

        catch (Exception e)
        {
             Do something.
        }

Any idea on what is going wrong here.(using C#+XAML+Win8)

Answer 1

HttpClient uses HttpWebRequest under the hood. It's likely that you're hitting the two concurrent connection limit of the HttpWebRequest's ServicePoint.

Answer 2

I got same issues once I do some change in package.appxmanifest > Capabilities

-> Enable Internet (Client & Server) option

After this application working fine.