HttpWebResponse.GetResponseHeader(String) Metoda

Definice

Obor názvů:

System.Net

Sestavení:

System.Net.Requests.dll

Zdroj:

HttpWebResponse.cs

Získá obsah hlavičky, která byla vrácena s odpovědí.

public:
 System::String ^ GetResponseHeader(System::String ^ headerName);

public string GetResponseHeader (string headerName);

member this.GetResponseHeader : string -> string

Public Function GetResponseHeader (headerName As String) As String

Parametry

headerName

String

Hodnota hlavičky, která se má vrátit.

Návraty

String

Obsah zadané hlavičky.

Výjimky

ObjectDisposedException

Aktuální instance byla odstraněna.

Příklady

Tento příklad vytvoří webový požadavek a dotazuje se na odpověď. Pokud web vyžaduje ověření, bude tento příklad reagovat řetězcem výzvy. Tento řetězec se extrahuje pomocí GetResponseHeader.

void GetPage( String^ url )
{
   try
   {
      Uri^ ourUri = gcnew Uri( url );
      // Creates an HttpWebRequest for the specified URL.
      HttpWebRequest^ myHttpWebRequest = (HttpWebRequest^)( WebRequest::Create( ourUri ) );
      HttpWebResponse^ myHttpWebResponse = (HttpWebResponse^)( myHttpWebRequest->GetResponse() );
      Console::WriteLine( "\nThe server did not issue any challenge.  Please try again with a protected resource URL." );
      // Releases the resources of the response.
      myHttpWebResponse->Close();
   }
   catch ( WebException^ e ) 
   {
      HttpWebResponse^ response = (HttpWebResponse^)( e->Response );
      if ( response != nullptr )
      {
         if ( response->StatusCode == HttpStatusCode::Unauthorized )
         {
            String^ challenge = nullptr;
            challenge = response->GetResponseHeader( "WWW-Authenticate" );
            if ( challenge != nullptr )
                        Console::WriteLine( "\nThe following challenge was raised by the server: {0}", challenge );
         }
         else
         {
            Console::WriteLine( "\nThe following WebException was raised : {0}", e->Message );
         }
      }
      else
      {
         Console::WriteLine( "\nResponse Received from server was 0" );
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "\nThe following Exception was raised : {0}", e->Message );
   }
}

   public static void GetPage(String url)
    {
    try
            {	
                Uri ourUri = new Uri(url);
                // Creates an HttpWebRequest for the specified URL.
                HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(ourUri);
                HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
                Console.WriteLine("\nThe server did not issue any challenge.  Please try again with a protected resource URL.");
                // Releases the resources of the response.
                myHttpWebResponse.Close();
            }
        catch(WebException e)
           {
                HttpWebResponse response = (HttpWebResponse)e.Response;
                if (response != null)
                {
                    if (response.StatusCode == HttpStatusCode.Unauthorized)
                    {
                        string challenge = null;
                        challenge= response.GetResponseHeader("WWW-Authenticate");
                        if (challenge != null)
                            Console.WriteLine("\nThe following challenge was raised by the server:{0}",challenge);
                    }
                    else
                {
                    Console.WriteLine("\nThe following WebException was raised : {0}",e.Message);
                }
            }
                else
            {
                Console.WriteLine("\nResponse Received from server was null");
            }
        }
        catch(Exception e)
        {
            Console.WriteLine("\nThe following Exception was raised : {0}",e.Message);
        }
    }
}

Public Shared Sub GetPage(url As [String])
Try
        Dim ourUri As New Uri(url)
        ' Creates an HttpWebRequest for the specified URL. 
        Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create(ourUri), HttpWebRequest)
        Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
        Console.WriteLine(ControlChars.NewLine + "The server did not issue any challenge.  Please try again with a protected resource URL.")
        ' Releases the resources of the response.
        myHttpWebResponse.Close()
    Catch e As WebException
        Dim response As HttpWebResponse = CType(e.Response, HttpWebResponse)
        If Not (response Is Nothing) Then
            If response.StatusCode = HttpStatusCode.Unauthorized Then
                Dim challenge As String = Nothing
                challenge = response.GetResponseHeader("WWW-Authenticate")
                If Not (challenge Is Nothing) Then
                    Console.WriteLine(ControlChars.NewLine + "The following challenge was raised by the server:{0}", challenge)
                End If
            Else
                Console.WriteLine(ControlChars.NewLine + "The following exception was raised : {0}", e.Message)
            End If
        Else
            Console.WriteLine(ControlChars.NewLine + "Response Received from server was null")
        End If 
    Catch e As Exception
        Console.WriteLine(ControlChars.NewLine + "The following exception was raised : {0}", e.Message)
    End Try
End Sub

Poznámky

Slouží GetResponseHeader k načtení obsahu konkrétních hlaviček. Musíte zadat hlavičku, kterou chcete vrátit.