TcpListener.Pending Metode

Definisi

Ruang nama:

System.Net.Sockets

Rakitan:

System.Net.Sockets.dll

Sumber:

TCPListener.cs

Menentukan apakah ada permintaan koneksi yang tertunda.

public:
 bool Pending();

public bool Pending ();

member this.Pending : unit -> bool

Public Function Pending () As Boolean

Mengembalikan

Boolean

true jika koneksi tertunda; jika tidak, false.

Pengecualian

InvalidOperationException

Pendengar belum dimulai dengan panggilan ke Start().

Contoh

Contoh kode berikut memeriksa Pending metode . Jika permintaan koneksi menunggu untuk diterima, maka panggilan ke AcceptTcpClient metode akan dilakukan.

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())

Keterangan

Metode non-pemblokiran ini menentukan apakah ada permintaan koneksi yang tertunda. AcceptSocket Karena metode dan AcceptTcpClient memblokir eksekusi sampai Start metode telah mengantre permintaan koneksi masuk, Pending metode dapat digunakan untuk menentukan apakah koneksi tersedia sebelum mencoba menerimanya.

Lihat juga

• Start()
• AcceptSocket()
• AcceptTcpClient()