C# HttpClient GetAsync 異常“服務器返回無效或無法識別的響應”

Question

這似乎是一個隨機問題。 有時 GetAsync 會成功獲得響應 (200/OK)。 其他時候它會拋出異常。 我認為這與“傳輸編碼：分塊”有關。 順便說一句...流式文件的大小從 8MB 到 300MB

這是我的相關代碼：

HttpResponseMessage response = null;
try
{
    HttpClient httpClient = new HttpClient
    {
        Timeout = TimeSpan.FromSeconds(60)
    };
    httpClient.DefaultRequestHeaders.Add("Accept", "multipart/related; type=\"application/dicom\"");
    response = await httpClient.GetAsync(uri);
    if (response.StatusCode != HttpStatusCode.OK)
    {
        Console.WriteLine($"Response:[{response}]");
        return false;
    }
}
catch (Exception e)
{
    Console.WriteLine($"Exception:[{e.Message}] | Stack:[{e.StackTrace}] | InnerEx:[{e.InnerException}]");
    return false;
}

這是 GetAsync 成功（200/OK）時的 HttpResponseMessage：

{
  "Version": {
    "Major": 1,
    "Minor": 1,
    "Build": -1,
    "Revision": -1,
    "MajorRevision": -1,
    "MinorRevision": -1
  },
  "Content": {
    "Headers": [
      {
        "Key": "Content-Type",
        "Value": [ "multipart/related; boundary=Boundary_77_676776408_1611644859244; type=\"application/dicom\"" ]
      }
    ]
  },
  "StatusCode": 200,
  "ReasonPhrase": "OK",
  "Headers": [
    {
      "Key": "Transfer-Encoding",
      "Value": [ "chunked" ]
    },
    {
      "Key": "MIME-Version",
      "Value": [ "1.0" ]
    },
    {
      "Key": "Date",
      "Value": [ "Tue, 26 Jan 2021 07:07:39 GMT" ]
    },
    {
      "Key": "Proxy-Connection",
      "Value": [ "Keep-Alive" ]
    },
    {
      "Key": "Connection",
      "Value": [ "Keep-Alive" ]
    },
    {
      "Key": "Age",
      "Value": [ "0" ]
    }
  ],
  "RequestMessage": {
    "Version": {
      "Major": 2,
      "Minor": 0,
      "Build": -1,
      "Revision": -1,
      "MajorRevision": -1,
      "MinorRevision": -1
    },
    "Content": null,
    "Method": { "Method": "GET" },
    "RequestUri": "http://1.2.3.4:5007/blah/blah1/11/blah2/22/blah3/33",
    "Headers": [
      {
        "Key": "Accept",
        "Value": [ "multipart/related; type=\"application/dicom\"" ]
      }
    ],
    "Properties": {}
  },
  "IsSuccessStatusCode": true
}

其他時候沒有響應並拋出異常：

異常：[服務器返回無效或無法識別的響應。] | Stack:[ at System.Net.Http.HttpConnection.ThrowInvalidHttpResponse() at System.Net.Http.HttpConnection.ChunkedEncodingReadStream.ReadChunkFromConnectionBuffer(Int32 maxBytesToRead, CancellationTokenRegistration cancellationRegistration) at System.Net.Http.HttpConnection.ChunkedEncodingReadStream.CopyToAsyncCore(Stream destination, CancellationToken cancellationToken) at System.Net.Http.HttpConnection.HttpConnectionResponseContent.SerializeToStreamAsync(Stream stream, TransportContext context, CancellationToken cancellationToken) at System.Net.Http.HttpContent.LoadIntoBufferAsyncCore(Task serializeToStreamTask, MemoryStream tempBuffer) at System.Net.Http.HttpClient .FinishSendAsyncBuffered(Task`1 sendTask, HttpRequestMessage 請求, CancellationTokenSource cts, Z27226C864BAC7454A850 4F8EDB15D95BZ disposeCts) 在 myapp.GetBlahAsync(Uri uri, String newFileName) 在 C:\blah\Svc.cs:line 97] | 內殼：[]

Answer 1

是因為你需要反序列化響應

   HttpResponseMessage response = null;
try
{
    HttpClient httpClient = new HttpClient {
        Timeout = TimeSpan.FromSeconds(60)
    };
    httpClient.DefaultRequestHeaders.Add("Accept", "multipart/related; type=\"application/dicom\"");
    response = await httpClient.GetAsync(uri);
    if (response.IsSuccessStatusCode)
    {

        var responseData = await response.Content.ReadAsStringAsync();
        var options = new JsonSerializerOptions() { PropertyNameCaseInsensitive = true };
        var result = JsonSerializer.Deserialize<Root>(responseData, options);

        Console.WriteLine($"Response:[{result }]");
        return result;
    }
}
catch (Exception e)
{
    Console.WriteLine($"Exception:[{e.Message}] | Stack:[{e.StackTrace}] | InnerEx:[{e.InnerException}]");
    return false;
}

for convert your json to c# class use this site Json to c# class

  // Root myDeserializedClass = JsonConvert.DeserializeObject<Root>(myJsonResponse); 
        public class Version    {
            public int Major { get; set; } 
            public int Minor { get; set; } 
            public int Build { get; set; } 
            public int Revision { get; set; } 
            public int MajorRevision { get; set; } 
            public int MinorRevision { get; set; } 
        }
    
        public class Header    {
            public string Key { get; set; } 
            public List<string> Value { get; set; } 
        }
    
        public class Content    {
            public List<Header> Headers { get; set; } 
        }
    
        public class Method    {
            public string Method { get; set; } 
        }
    
        public class Properties    {
        }
    
        public class RequestMessage    {
            public Version Version { get; set; } 
            public object Content { get; set; } 
            public Method Method { get; set; } 
            public string RequestUri { get; set; } 
            public List<Header> Headers { get; set; } 
            public Properties Properties { get; set; } 
        }
    
        public class Root    {
            public Version Version { get; set; } 
            public Content Content { get; set; } 
            public int StatusCode { get; set; } 
            public string ReasonPhrase { get; set; } 
            public List<Header> Headers { get; set; } 
            public RequestMessage RequestMessage { get; set; } 
            public bool IsSuccessStatusCode { get; set; } 
        }

或在 Visual Studio 中的Edit-->Paste Special-->Paste JSON As Classes