TcpListener.Pending Methode

Definition

Bestimmt, ob ausstehende Verbindungsanforderungen vorliegen.Determines if there are pending connection requests.

public:
 bool Pending();
public bool Pending ();
member this.Pending : unit -> bool
Public Function Pending () As Boolean

Gibt zurück

Boolean

true, wenn Verbindungen ausstehen, andernfalls false.true if connections are pending; otherwise, false.

Ausnahmen

Der Listener wurde nicht mit einem Aufruf von Start() gestartet.The listener has not been started with a call to Start().

Beispiele

Im folgenden Codebeispiel wird die- Pending Methode überprüft.The following code example checks the Pending method. Wenn eine Verbindungsanforderung darauf wartet, akzeptiert zu werden, wird ein Rückruf der- AcceptTcpClient Methode durchgeführt.If a connection request is waiting to be accepted, then a call to the AcceptTcpClient method is made.

try
{
   // Use the Pending method to poll the underlying socket instance for client connection requests.
   TcpListener^ tcpListener = gcnew TcpListener( portNumber );
   tcpListener->Start();

   if ( !tcpListener->Pending() )
   {
      Console::WriteLine( "Sorry, no connection requests have arrived" );
   }
   else
   {
      //Accept the pending client connection and return a TcpClient object^ initialized for communication.
      TcpClient^ tcpClient = tcpListener->AcceptTcpClient();
      
      // Using the RemoteEndPoint property.
      Console::WriteLine( "I am listening for connections on {0} on port number {1}",
         IPAddress::Parse( ( (IPEndPoint^)(tcpListener->LocalEndpoint) )->Address->ToString() ),
         ( (IPEndPoint^)(tcpListener->LocalEndpoint) )->Port );
        
try{
        // Use the Pending method to poll the underlying socket instance for client connection requests.
          IPAddress ipAddress = Dns.Resolve("localhost").AddressList[0];
      TcpListener tcpListener =  new TcpListener(ipAddress, portNumber); 
      tcpListener.Start();
      
          if (!tcpListener.Pending()) {

          Console.WriteLine("Sorry, no connection requests have arrived");
       }
       else{

             //Accept the pending client connection and return a TcpClient object initialized for communication.
             TcpClient tcpClient = tcpListener.AcceptTcpClient();
             // Using the RemoteEndPoint property.
             Console.WriteLine("I am listening for connections on " + 
                                         IPAddress.Parse(((IPEndPoint)tcpListener.LocalEndpoint).Address.ToString()) +
                                          "on port number " + ((IPEndPoint)tcpListener.LocalEndpoint).Port.ToString());


Try

   Dim ipAddress As IPAddress = Dns.Resolve("localhost").AddressList(0)
  Dim tcpListener As New TcpListener(ipAddress, portNumber)
  tcpListener.Start()
  
   ' Use the Pending method to poll the underlying socket instance for client connection requests.
   If Not tcpListener.Pending() Then
      
      Console.WriteLine("Sorry, no connection requests have arrived")
   
   Else
      
      'Accept the pending client connection and return a TcpClient object initialized for communication.
      Dim tcpClient As TcpClient = tcpListener.AcceptTcpClient()
      ' Using the RemoteEndPoint property.
      Console.Write("I am listening for connections on ")
      Console.Writeline(IPAddress.Parse(CType(tcpListener.LocalEndpoint, IPEndPoint).Address.ToString())) 
      Console.Write("on port number ")
      Console.Write(CType(tcpListener.LocalEndpoint, IPEndPoint).Port.ToString())
      

Hinweise

Diese nicht blockierende Methode bestimmt, ob ausstehende Verbindungsanforderungen vorhanden sind.This non-blocking method determines if there are any pending connection requests. Da die AcceptSocket -und- AcceptTcpClient Methoden die Ausführung blockieren, bis die- Start Methode eine eingehende Verbindungsanforderung in die Warteschlange eingereiht hat, kann die- Pending Methode verwendet werden, um zu bestimmen, ob Verbindungen verfügbar sind, bevor SieBecause the AcceptSocket and AcceptTcpClient methods block execution until the Start method has queued an incoming connection request, the Pending method can be used to determine if connections are available before attempting to accept them.

Gilt für:

Weitere Informationen