HTTPWebRequest＆過了一會兒，400（錯誤請求）啟動

Question

我有一個后台工作線程，它不斷地將數據同步到遠程服務器或從遠程服務器同步數據。 當我第一次運行應用程序時，一切似乎都正常。 它每30秒發出一次Web請求，數據返回成功。

如果我讓模擬器長時間運行，最終請求將因（400）錯誤請求而失敗。 所有后續請求都做同樣的事情。 如果我殺了應用程序並重新啟動它...一切都很好。

有人有想法么？ 代碼如下。

public RestResponse<T> Execute<T>(RestRequest request) {
    var restResponse = new RestResponse<T>();
    var serializer = new JavaScriptSerializer();
    var urlPath = baseUrl + "/" + request.Resource;
    Console.WriteLine("Requesting: " + urlPath);
    var httpRequest = (HttpWebRequest)HttpWebRequest.Create(new Uri(urlPath));

    httpRequest.Headers = request.Headers;
    foreach (string key in clientHeaders.Keys)
        httpRequest.Headers.Add(key, clientHeaders[key]);
    httpRequest.Headers.Add("Accept-Encoding", "gzip,deflate");

    Authenticator.Authenticate(httpRequest);
    httpRequest.Method = request.Method.ToString();       
    HttpWebResponse httpResponse = null;
    try {
        if ((request.Method == Method.POST) && (!request.IsJsonPost))
            SetPostData(httpRequest, request);

        if ((request.Method == Method.POST) && (request.IsJsonPost)){
            SetJsonPostData(httpRequest, request);
        }

        httpResponse = (HttpWebResponse)httpRequest.GetResponse();
        var reader = new StreamReader(GetStreamForResponse(httpResponse));
        var responseString = reader.ReadToEnd();
        Console.WriteLine(responseString);
        reader.Close();
        restResponse.StatusCode = httpResponse.StatusCode;
        restResponse.Headers = httpResponse.Headers;
        restResponse.Data = serializer.Deserialize<T>(responseString);
        restResponse.ResponseStatus = ResponseStatus.Completed;
        httpResponse.Close();
    } catch (WebException e) {
        restResponse.ResponseStatus = ResponseStatus.Error;
        restResponse.ErrorMessage = e.Message;
        restResponse.ErrorException = e;
        var webResponse = (HttpWebResponse)e.Response;
        if (webResponse != null) {
            restResponse.StatusCode = webResponse.StatusCode;
            restResponse.Headers = webResponse.Headers;
        }
        if (restResponse.StatusCode != HttpStatusCode.NotModified)
            Console.WriteLine("An exception occured:\r\n " + request.Resource + "\r\n" + e + "\r\n");
    } catch (Exception ex) {
        restResponse.ResponseStatus = ResponseStatus.Error;
        restResponse.ErrorMessage = ex.Message;
        restResponse.ErrorException = ex;
    }

    if (httpResponse != null)
        httpResponse.Close();

    return restResponse;
}

它失敗了：

httpResponse = (HttpWebResponse)httpRequest.GetResponse();

堆棧跟蹤：

System.Net.WebException: The remote server returned an error: (400) Bad Request.
  at System.Net.HttpWebRequest.CheckFinalStatus (System.Net.WebAsyncResult result) [0x002f2] in /Developer/MonoTouch/Source/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1477 
  at System.Net.HttpWebRequest.SetResponseData (System.Net.WebConnectionData data) [0x00141] in /Developer/MonoTouch/Source/mono/mcs/class/System/System.Net/HttpWebRequest.cs:1300 

請求永遠不會到達遠程服務器。

Answer 1

問題出在clientHeaders集合中。 此RESTClient類在應用程序生命周期中實例化一次。 我一遍又一遍地添加標題而不是先清除它們。 過了一會兒，標題太大了，發出了錯誤的請求。

Answer 2

我假設你沒有連接。 你可以嘗試增加它們：

<configuration> <system.net> <connectionManagement> <add address="*" maxconnection="65535" /> </connectionManagement> </system.net> </configuration>