FtpWebResponse.ContentLength Eigenschaft

Definition

Ruft die Länge der vom FTP-Server empfangenen Daten ab.Gets the length of the data received from the FTP server.

public:
 virtual property long ContentLength { long get(); };
public override long ContentLength { get; }
member this.ContentLength : int64
Public Overrides ReadOnly Property ContentLength As Long

Eigenschaftswert

Ein Int64-Wert, der die Anzahl von Bytes der vom FTP-Server empfangenen Daten enthält.An Int64 value that contains the number of bytes of data received from the FTP server.

Beispiele

Im folgenden Codebeispiel wird eine Datei von auf dem angegebenen FTP-Server heruntergeladen.The following code example downloads a file from on the specified FTP server. Diese Eigenschaft enthält die Anzahl der Bytes in der heruntergeladenen Datei.This property contains the number of bytes in the downloaded file.

static bool DownloadFileFromServer( Uri^ serverUri, String^ localFileName )
{
   // The serverUri parameter should start with the ftp:// scheme.
   if ( serverUri->Scheme != Uri::UriSchemeFtp )
   {
      return false;
   }

   // Get the object used to communicate with the server.
   // Note that the cast to FtpWebRequest is done only
   // for the purposes of illustration. If your application
   // does not set any properties other than those defined in the
   // System.Net.WebRequest class, you can use the following line instead:
   // WebRequest request = WebRequest.Create(serverUri);
   //
   FtpWebRequest^ request = dynamic_cast<FtpWebRequest^>(WebRequest::Create( serverUri ));
   request->Method = WebRequestMethods::Ftp::DownloadFile;
   FtpWebResponse^ response = dynamic_cast<FtpWebResponse^>(request->GetResponse());
   Stream^ responseStream = nullptr;
   StreamReader^ readStream = nullptr;
   StreamWriter^ writeStream = nullptr;
   try
   {
      responseStream = response->GetResponseStream();
      readStream = gcnew StreamReader( responseStream,System::Text::Encoding::UTF8 );
      
      // Display information about the data received from the server.
      Console::WriteLine( "Bytes received: {0}", response->ContentLength );
      Console::WriteLine( "Message from server: {0}", response->StatusDescription );
      Console::WriteLine( "Resource: {0}", response->ResponseUri );

      // Write the bytes received from the server to the local file.
      if ( readStream != nullptr )
      {
         writeStream = gcnew StreamWriter( localFileName,false );
         writeStream->Write( readStream->ReadToEnd() );
      }
   }
   finally
   {
      if ( readStream != nullptr )
      {
         readStream->Close();
      }

      if ( response != nullptr )
      {
         response->Close();
      }

      if ( writeStream != nullptr )
      {
         writeStream->Close();
      }
   }

   return true;
}
public static bool DownloadFileFromServer(Uri serverUri, string localFileName)
{
    // The serverUri parameter should start with the ftp:// scheme.
    if (serverUri.Scheme != Uri.UriSchemeFtp)
    {
        return false;
    }
    // Get the object used to communicate with the server.
    // Note that the cast to FtpWebRequest is done only
    // for the purposes of illustration. If your application
    // does not set any properties other than those defined in the
    // System.Net.WebRequest class, you can use the following line instead:
    // WebRequest request = WebRequest.Create(serverUri);
    //
    FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
    request.Method = WebRequestMethods.Ftp.DownloadFile;
    
    FtpWebResponse response = (FtpWebResponse) request.GetResponse();
    
    Stream responseStream = null;
    StreamReader readStream = null;
    StreamWriter writeStream = null;
    try
    {
        responseStream = response.GetResponseStream(); 
        readStream = new StreamReader(responseStream, System.Text.Encoding.UTF8);
        // Display information about the data received from the server.
        Console.WriteLine("Bytes received: {0}",response.ContentLength);   
         
        Console.WriteLine("Message from server: {0}", response.StatusDescription);
        Console.WriteLine("Resource: {0}", response.ResponseUri);
       
        // Write the bytes received from the server to the local file.
        if (readStream != null)
        {
            writeStream = new StreamWriter(localFileName, false);
            writeStream.Write(readStream.ReadToEnd());
        }
    }
    finally
    {
        if (readStream != null)
        {
            readStream.Close();
        }
        if (response != null)
        {
            response.Close();
        }
        if (writeStream != null)
        {
            writeStream.Close();
        }
    }
    return true;
}

Hinweise

Wenn ein Antwortdaten Strom vom FTP-Server zurückgegeben wird, enthält die ContentLength-Eigenschaft die Anzahl der Bytes im Stream.When a response stream is returned by the FTP server, the ContentLength property contains the number of bytes in the stream. ContentLength gibt "− 1" zurück, wenn in der Antwort keine Daten zurückgegeben wurden, oder wenn der Server keine Inhalts Längen Informationen gesendet hat.ContentLength returns −1 if no data was returned in the response or if the server did not send content length information. Der Rückgabewert ist größer als oder gleich 0 (null), wenn die Daten zurückgegeben werden oder sollen.The return value is greater than or equal to zero if data was or should have been returned. Bei Anforderungen, die das ListDirectory-Feld verwenden, gibt die ContentLength-Eigenschaft immer "− 1" zurück.For example, for requests that use the ListDirectory field, the ContentLength property always returns −1. Bei Anforderungen, die die UploadFile-Methode verwenden, ist die ContentLength-Eigenschaft immer 0 (null).For requests that use the UploadFile method, the ContentLength property is always zero. Bei Anforderungen, die die DownloadFile-Methode verwenden, ist die-Eigenschaft größer als 0 (null), wenn die heruntergeladene Datei Daten enthielt und NULL ist, wenn Sie leer war.For requests that use the DownloadFile method, the property is greater than zero if the downloaded file contained data and is zero if it was empty.

Bei Anforderungen, die die GetFileSize-Methode verwenden, gibt ContentLength die Größe der angegebenen Datei auf dem Server zurück.For requests that use the GetFileSize method, ContentLength returns the size of the specified file on the server.

Gilt für:

Siehe auch