WebException-Konstruktor (String)

Initialisiert eine neue Instanz der WebException-Klasse mit der angegebenen Fehlermeldung.

Namespace: System.Net
Assembly: System (in system.dll)

Syntax

'Declaration
Public Sub New ( _
    message As String _
)
'Usage
Dim message As String

Dim instance As New WebException(message)

public WebException (
    string message
)

public:
WebException (
    String^ message
)

public WebException (
    String message
)

public function WebException (
    message : String
)

Parameter

• message
  Der Text der Fehlermeldung.

Hinweise

Die WebException-Instanz wird initialisiert, wobei die Message-Eigenschaft auf den Wert von message festgelegt wird. Wenn message NULL (Nothing in Visual Basic) ist, wird die Message-Eigenschaft mit einer vom System bereitgestellten Meldung initialisiert. Die InnerException-Eigenschaft und die Response-Eigenschaft werden mit NULL (Nothing in Visual Basic) initialisiert. Die Status-Eigenschaft wird mit RequestCanceled initialisiert.

Beispiel

Im folgenden Beispiel wird eine WebException durch Angabe einer Fehlermeldung ausgelöst.

Try
    ' A 'Socket' object has been created.
    Dim httpSocket As New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
    
    ' The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
      
    Dim hostEntry As IPHostEntry = Dns.Resolve(connectUri)
    
    Dim serverAddress As IPAddress = hostEntry.AddressList(0)
    Dim endPoint As New IPEndPoint(serverAddress, 80)
    httpSocket.Connect(endPoint)
    Console.WriteLine("Connection created successfully")
    httpSocket.Close()
Catch e As SocketException
    Console.WriteLine((ControlChars.Cr + "Exception thrown." + ControlChars.Cr + "The Original Message is: " + e.Message))
    ' Throw the 'WebException' object with a message string specific to the situation.
    Throw New WebException("Unable to locate the Server with 'www.contoso.com' Uri.")
End Try

 try
{
     // A 'Socket' object has been created.
     Socket httpSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

     // The IPaddress of the unknown uri is resolved using the 'Dns.Resolve' method. 
     IPHostEntry hostEntry = Dns.Resolve(connectUri);

     IPAddress serverAddress = hostEntry.AddressList[0];
     IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
      httpSocket.Connect(endPoint);
     Console.WriteLine("Connection created successfully");
     httpSocket.Close();
  }
catch(SocketException e)
  {             
     Console.WriteLine("\nException thrown.\nThe Original Message is: "+e.Message);
     // Throw the 'WebException' object with a message string specific to the situation.
     throw new WebException("Unable to locate the Server with 'www.contoso.com' Uri.");
  }

try
{
   // A 'Socket' object has been created.
   Socket^ httpSocket = gcnew Socket( AddressFamily::InterNetwork, SocketType::Stream, ProtocolType::Tcp );
   
   // The IPaddress of the unknown uri is resolved using the 'Dns::Resolve' method.
   IPHostEntry^ hostEntry = Dns::Resolve( connectUri );

   IPAddress^ serverAddress = hostEntry->AddressList[ 0 ];
   IPEndPoint^ endPoint = gcnew IPEndPoint( serverAddress, 80 );
   httpSocket->Connect( endPoint );
   Console::WriteLine( "Connection created successfully" );
   httpSocket->Close();
}
catch ( SocketException^ e ) 
{
   Console::WriteLine( "\nException thrown.\nThe Original Message is: {0}", e->Message );
   
   // Throw the 'WebException' object with a message string specific to the situation.
   throw gcnew WebException( "Unable to locate the Server with 'www.contoso.com' Uri." );
}

try {
    // A 'Socket' object has been created.
    Socket httpSocket = new Socket(AddressFamily.InterNetwork,
        SocketType.Stream, ProtocolType.Tcp);
    // The IPaddress of the unknown uri is resolved using the 
    // 'Dns.Resolve' method. 
    IPHostEntry hostEntry = Dns.Resolve(connectUri);
    IPAddress serverAddress = (IPAddress)hostEntry.
        get_AddressList().get_Item(0);
    IPEndPoint endPoint = new IPEndPoint(serverAddress, 80);
    httpSocket.Connect(endPoint);
    Console.WriteLine("Connection created successfully");
    httpSocket.Close();
}
catch (SocketException e) {
    Console.WriteLine("\nException thrown.\nThe Original Message is: " 
        + e.get_Message());
    // Throw the 'WebException' object with a message string 
    // specific to the situation.
    throw new WebException("Unable to locate the Server with" 
        + " 'www.contoso.com' Uri.");
}

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

WebException-Klasse
WebException-Member
System.Net-Namespace
Exception