My Windows Phone app Get empty response (404 Not Found) Scond time, work's great first time;And always work fine if without SSL

Question

I am building my first windowsPhone 8.1 application ,the role of my application is to create connection with server to get information from it, so I am writing the code to do this process by sending json-rpc request to server to get some information ,I am successful to get it in first time but when I send the second request I am receiving an empty response with 404 error (page not found). But when I call the service without https (http only) it works fine regardless how many time I call it !

   public async Task<string> GetDataFromServer(string urlToCall, string JSONData,string RR)
        {
            string UserName = “XXXXXXX”
            string Password = "XXX";

            using ( var handler = new HttpClientHandler())
            {
                handler.Credentials = new NetworkCredential(UserName, Password);
                HttpClient client = new HttpClient(handler);

                HttpResponseMessage response = null;

            try
            {


                response = await client.PostAsync(urlToCall, new StringContent(JSONData.ToString(), Encoding.UTF8, " application/json"));
               string res = response.Content.ReadAsStringAsync().Result;




                Windows.UI.Popups.MessageDialog g = new Windows.UI.Popups.MessageDialog(res);
                await g.ShowAsync();
                return res;

            }
            catch (Exception ex)
            {


                Windows.UI.Popups.MessageDialog g = new Windows.UI.Popups.MessageDialog("Error is : " + ex.Message);
               g.ShowAsync();
               return "Error";
            }
            finally
            {
                response.Dispose();
                client.CancelPendingRequests();
                client.Dispose();
                handler.Dispose();
            }
            }

        }

Again, when call the URL of service (start with https) on first time I got response with seeked data, but second time I receive an empty response with 404 error (page not found) !! Any help please

It should not return 404 for the second time if the input parameters passed in the method are same.. can you check the uriToCall parameter value in second call? — Muhammad Saifullah, Jun 04 '14 at 13:46
Shoot in the dark - maybe problem with some cache. Have you tried: [like in this answer](http://stackoverflow.com/a/21255975/2681948), also [here](http://stackoverflow.com/a/20730376/2681948)? — Romasz, Jun 04 '14 at 17:14
I found it work find without SSL regardless how many time I call it, but when call the https (with SSL) it is not working! — Bashar Abu Shamaa, Jun 08 '14 at 10:01

score 3 · Accepted Answer · answered Jun 23 '14 at 07:25

Please try to use this solution.

        public async Task<string> SendJSONData3(string urlToCall, string JSONData)
    {
        string UserName = "XXXXXXXXX";
        string Password = "XXXXXXXXX";
        var httpWebRequest = (HttpWebRequest)WebRequest.Create(urlToCall);
        httpWebRequest.Credentials = new NetworkCredential(UserName, Password);
        httpWebRequest.ContentType = "text/json";
        httpWebRequest.Method = "POST";
        using (var streamWriter = new StreamWriter(await httpWebRequest.GetRequestStreamAsync()))
        {
            string json = JSONData;
            streamWriter.Write(json);
            streamWriter.Flush();
        }
        var httpResponse = (HttpWebResponse)await httpWebRequest.GetResponseAsync();
        using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
        {
            var result = streamReader.ReadToEnd();
            return result;
        }

    }

score 1 · Answer 2 · edited May 23 '17 at 10:33

1

A couple of ideas:

Do not use the .Result property. Just use await instead to avoid deadlocks.
Remove the additional space in front of the media type parameter " application/json"
Enable logging on the webserver and see if the second request arrives on the server.
Get a network trace, for example with Wireshark or Fiddler.
Try puting WebRequest.RegisterPrefix("https://", WebRequestCreator.ClientHttp); in your initialization code, as proposed in this answer.

edited May 23 '17 at 10:33

Community

1
1

answered Jun 19 '14 at 22:08

Simon

1,814
20
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1

Thank you so much for your response ,But regarding WebRequest in your last point, I don't use WebRequest in my code because it is not supported in Windows Phone 8.1 as it seems,and all my code depend on Http Client Class so what I could to be benefited by WebRequest Please help me – Bashar Abu Shamaa Jun 22 '14 at 13:20

My Windows Phone app Get empty response (404 Not Found) Scond time, work's great first time;And always work fine if without SSL

2 Answers2