處理在GetStringAsync

Question

HTTP響應代碼我很新的C＃，更不用說Windows Phone的開發:)

我試圖發送一個請求，得到JSON響應，但是如果有錯誤（例如作爲401），能夠告訴用戶這樣的。這裏是我的代碼：

async Task<string> AccessTheWebAsync() 
     { 
      //builds the credentials for the web request 
      var credentials = new NetworkCredential(globalvars.username, globalvars.password); 
      var handler = new HttpClientHandler { Credentials = credentials }; 

      //calls the web request, stores and returns JSON content 
      HttpClient client = new HttpClient(handler); 
      Task<string> getStringTask = client.GetStringAsync("https://www.bla.com/content"); 

      String urlContents = await getStringTask; 

      return urlContents; 

     } 

我知道它一定是我做錯了，我發送請求和存儲響應的方式......但我只是不知道是什麼。

如果有錯誤，我得到一個一般： net_http_message_not_success_statuscode

謝謝！

Answer 1

而不是使用的HttpClient使用普通的好老的HttpWebRequest :)

async Task<string> AccessTheWebAsync() 
    { 

     HttpWebRequest req = WebRequest.CreateHttp("http://example.com/nodocument.html"); 
     req.Method = "GET"; 
     req.Timeout = 10000; 
     req.KeepAlive = true; 

     string content = null; 
     HttpStatusCode code = HttpStatusCode.OK; 

     try 
     { 
      using (HttpWebResponse response = (HttpWebResponse)await req.GetResponseAsync()) 
      { 
       using (StreamReader sr = new StreamReader(response.GetResponseStream())) 
        content = await sr.ReadToEndAsync(); 

       code = response.StatusCode; 
      } 
     } 
     catch (WebException ex) 
     { 

      using (HttpWebResponse response = (HttpWebResponse)ex.Response) 
      { 
       using (StreamReader sr = new StreamReader(response.GetResponseStream())) 
        content = sr.ReadToEnd(); 

       code = response.StatusCode; 
      } 

     } 

     //Here you have now content and code. 

     return content; 

    } 

Answer 2

你可以使用TE GetAsync（）方法，而不是GetStringAsync（）的。

HttpResponseMessage response = await client.GetAsync("https://www.bla.com/content"); 

if(!response.IsSuccessStatusCode) 
{ 
    if (response.StatusCode == HttpStatusCode.Unauthorized) 
    { 
     do something... 
    } 
} 
String urlContents = await response.Content.ReadAsStringAsync(); 

這樣你就可以利用HttpStatusCode枚舉來檢查返回的狀態碼。