System.Net.HttpWebRequest.EndGetResponse C# (CSharp) Метод

        public override WebResponse EndGetResponse(IAsyncResult asyncResult)
        {
            CheckAbort();

            if (asyncResult == null || !(asyncResult is Task<WebResponse>))
            {
                throw new ArgumentException(SR.net_io_invalidasyncresult, nameof(asyncResult));
            }

            if (Interlocked.Exchange(ref _endGetResponseCalled, 1) != 0)
            {
                throw new InvalidOperationException(SR.Format(SR.net_io_invalidendcall, "EndGetResponse"));
            }

            WebResponse response;
            try
            {
                response = ((Task<WebResponse>)asyncResult).GetAwaiter().GetResult();
            }
            catch (Exception ex)
            {
                throw WebException.CreateCompatibleException(ex);
            }

            return response;
        }

        public Task<WebResponse> GetResponseAsync(HttpWebRequest request, int timeoutMs)
        {
            if (timeoutMs > 0)
            {
                return GetResponseAsync(request, TimeSpan.FromMilliseconds(timeoutMs));
            }

            var tcs = new TaskCompletionSource<WebResponse>();

            try
            {
                request.BeginGetResponse(iar =>
                {
                    try
                    {
                        var response = (HttpWebResponse)request.EndGetResponse(iar);
                        tcs.SetResult(response);
                    }
                    catch (Exception exc)
                    {
                        tcs.SetException(exc);
                    }
                }, null);
            }
            catch (Exception exc)
            {
                tcs.SetException(exc);
            }

            return tcs.Task;
        }