FtpWebRequest.EnableSsl Propiedad

  • Referencia

Definición

Espacio de nombres:
System.Net
Ensamblado:
System.Net.Requests.dll
Ensamblado:
System.dll
Ensamblado:
netstandard.dll

Obtiene o establece un valor Boolean que especifica que se debe usar una conexión SSL.

public:
 property bool EnableSsl { bool get(); void set(bool value); };
public bool EnableSsl { get; set; }
member this.EnableSsl : bool with get, set
Public Property EnableSsl As Boolean

Valor de propiedad

Boolean

Es true si las transmisiones de datos y de control están cifradas; de lo contrario, es false. El valor predeterminado es false.

Excepciones

InvalidOperationException

La conexión al servidor FTP ya ha sido establecida.

Ejemplos

En el ejemplo de código siguiente se usa una conexión cifrada para descargar la lista de directorios de un servidor FTP.

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

   // Get the object used to communicate with the server.
   FtpWebRequest^ request = dynamic_cast<FtpWebRequest^>(WebRequest::Create( serverUri ));
   request->Method = WebRequestMethods::Ftp::ListDirectory;
   request->EnableSsl = true;

   // Get the ServicePoint object used for this request, and limit it to one connection.
   // In a real-world application you might use the default number of connections (2),
   // or select a value that works best for your application.
   ServicePoint^ sp = request->ServicePoint;
   Console::WriteLine( "ServicePoint connections = {0}.", sp->ConnectionLimit );
   sp->ConnectionLimit = 1;
   FtpWebResponse^ response = dynamic_cast<FtpWebResponse^>(request->GetResponse());
   Console::WriteLine( "The content length is {0}", response->ContentLength );

   // The following streams are used to read the data returned from the server.
   Stream^ responseStream = nullptr;
   StreamReader^ readStream = nullptr;
   responseStream = response->GetResponseStream();
   readStream = gcnew StreamReader( responseStream,System::Text::Encoding::UTF8 );

   // Display the data received from the server.
   Console::WriteLine( readStream->ReadToEnd() );
   Console::WriteLine( "List status: {0}", response->StatusDescription );
   readStream->Close();
   response->Close();

   Console::WriteLine( "Banner message: {0}", response->BannerMessage );

   Console::WriteLine( "Welcome message: {0}", response->WelcomeMessage );

   Console::WriteLine( "Exit message: {0}", response->ExitMessage );

   return true;
}

public static bool ListFilesOnServerSsl(Uri serverUri)
{
    // The serverUri should start with the ftp:// scheme.
    if (serverUri.Scheme != Uri.UriSchemeFtp)
    {
        return false;
    }
    // Get the object used to communicate with the server.
    FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
    request.Method = WebRequestMethods.Ftp.ListDirectory;
    request.EnableSsl = true;

    // Get the ServicePoint object used for this request, and limit it to one connection.
    // In a real-world application you might use the default number of connections (2),
    // or select a value that works best for your application.

    ServicePoint sp = request.ServicePoint;
    Console.WriteLine("ServicePoint connections = {0}.", sp.ConnectionLimit);
    sp.ConnectionLimit = 1;

    FtpWebResponse response = (FtpWebResponse) request.GetResponse();
     Console.WriteLine("The content length is {0}", response.ContentLength);
    // The following streams are used to read the data returned from the server.
    Stream responseStream = null;
    StreamReader readStream = null;
    try
    {
        responseStream = response.GetResponseStream();
        readStream = new StreamReader(responseStream, System.Text.Encoding.UTF8);

        if (readStream != null)
        {
            // Display the data received from the server.
            Console.WriteLine(readStream.ReadToEnd());
        }
        Console.WriteLine("List status: {0}",response.StatusDescription);
    }
    finally
    {
        if (readStream != null)
        {
            readStream.Close();
        }
        if (response != null)
        {
            response.Close();
        }
    }

    Console.WriteLine("Banner message: {0}",
        response.BannerMessage);

    Console.WriteLine("Welcome message: {0}",
        response.WelcomeMessage);

    Console.WriteLine("Exit message: {0}",
        response.ExitMessage);
    return true;
}

Comentarios

Precaución

A menos que la EnableSsl propiedad sea true, todos los datos y comandos, incluidos el nombre de usuario y la información de contraseña, se envían al servidor en texto no cifrado. Cualquier persona que supervise el tráfico de red puede ver sus credenciales y usarlas para conectarse al servidor. Si se conecta a un servidor FTP que requiere credenciales y admite SSL, debe establecer en EnableSsltrue.

El "AUTH TLS" comando se envía al servidor para solicitar una sesión cifrada. Si el servidor no reconoce este comando, recibirá una WebException excepción.

Se aplica a

Consulte también