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TcpListener.Pending Método

  • Referencia

Definición

Espacio de nombres:
System.Net.Sockets
Ensamblado:
System.Net.Sockets.dll
Ensamblado:
System.dll
Ensamblado:
netstandard.dll
Source:
TCPListener.cs
Source:
TCPListener.cs
Source:
TCPListener.cs

Determina si existen solicitudes de conexión pendientes.

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

Devoluciones

Boolean

Es true si hay conexiones pendientes; en caso contrario, es false.

Excepciones

InvalidOperationException

El agente de escucha no se ha iniciado con una llamada a Start().

Ejemplos

En el ejemplo de código siguiente se comprueba el Pending método . Si se acepta una solicitud de conexión, se realiza una llamada al AcceptTcpClient método .

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 );

const int portNumber = 13;

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());

        //Close the tcpListener and tcpClient instances
        tcpClient.Close();
    }

    tcpListener.Stop();
}
catch (Exception e)
{
    Console.WriteLine(e.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())

Comentarios

Este método de no bloqueo determina si hay solicitudes de conexión pendientes. Dado que los métodos y bloquean la AcceptSocket ejecución hasta que el Start método ha puesto en cola una solicitud de conexión entrante, el Pending método se puede usar para determinar si las conexiones están disponibles antes de intentar aceptarlas.AcceptTcpClient

Se aplica a

Consulte también