UdpClient.Receive(IPEndPoint) 方法

定義

命名空間:

System.Net.Sockets

組件:

System.Net.Sockets.dll

來源:

UDPClient.cs

傳回由遠端主機傳送的 UDP 資料包。

public:
 cli::array <System::Byte> ^ Receive(System::Net::IPEndPoint ^ % remoteEP);

public byte[] Receive (ref System.Net.IPEndPoint? remoteEP);

member this.Receive : IPEndPoint -> byte[]

Public Function Receive (ByRef remoteEP As IPEndPoint) As Byte()

參數

remoteEP

IPEndPoint

IPEndPoint，表示傳送資料的遠端主機。

傳回

Byte[]

Byte 型別的陣列，包含資料包資料。

例外狀況

ObjectDisposedException

基礎 Socket 已關閉。

SocketException

存取通訊端時發生錯誤。

範例

下列範例示範 Receive 方法。 方法會 Receive 封鎖執行，直到收到訊息為止。 IPEndPoint使用 傳遞至 Receive的 ，就會顯示回應主機的身分識別。

//Creates a UdpClient for reading incoming data.
UdpClient^ receivingUdpClient = gcnew UdpClient( 11000 );

//Creates an IPEndPoint to record the IP Address and port number of the sender. 
// The IPEndPoint will allow you to read datagrams sent from any source.
IPEndPoint^ RemoteIpEndPoint = gcnew IPEndPoint( IPAddress::Any,0 );
try
{
   // Blocks until a message returns on this socket from a remote host.
   array<Byte>^receiveBytes = receivingUdpClient->Receive(  RemoteIpEndPoint );

   String^ returnData = Encoding::ASCII->GetString( receiveBytes );

   Console::WriteLine( "This is the message you received {0}", returnData );
   Console::WriteLine( "This message was sent from {0} on their port number {1}",
      RemoteIpEndPoint->Address, RemoteIpEndPoint->Port );
}
catch ( Exception^ e ) 
{
   Console::WriteLine( e->ToString() );
}

 //Creates a UdpClient for reading incoming data.
 UdpClient receivingUdpClient = new UdpClient(11000);

 //Creates an IPEndPoint to record the IP Address and port number of the sender.
// The IPEndPoint will allow you to read datagrams sent from any source.
 IPEndPoint RemoteIpEndPoint = new IPEndPoint(IPAddress.Any, 0);
 try{

     // Blocks until a message returns on this socket from a remote host.
     Byte[] receiveBytes = receivingUdpClient.Receive(ref RemoteIpEndPoint);

     string returnData = Encoding.ASCII.GetString(receiveBytes);

     Console.WriteLine("This is the message you received " +
                               returnData.ToString());
     Console.WriteLine("This message was sent from " +
                                 RemoteIpEndPoint.Address.ToString() +
                                 " on their port number " +
                                 RemoteIpEndPoint.Port.ToString());
 }
 catch ( Exception e ){
     Console.WriteLine(e.ToString());
 }

   'Creates a UdpClient for reading incoming data.
   Dim receivingUdpClient As New UdpClient(11000)
   
   'Creates an IPEndPoint to record the IP address and port number of the sender. 
   ' The IPEndPoint will allow you to read datagrams sent from any source.
   Dim RemoteIpEndPoint As New IPEndPoint(IPAddress.Any, 0)
   Try
      
      ' Blocks until a message returns on this socket from a remote host.
      Dim receiveBytes As [Byte]() = receivingUdpClient.Receive(RemoteIpEndPoint)
      
      Dim returnData As String = Encoding.ASCII.GetString(receiveBytes)
      
      Console.WriteLine(("This is the message you received " + returnData.ToString()))
      Console.WriteLine(("This message was sent from " + RemoteIpEndPoint.Address.ToString() + " on their port number " + RemoteIpEndPoint.Port.ToString()))
   Catch e As Exception
      Console.WriteLine(e.ToString())
   End Try
End Sub

備註

方法 Receive 會封鎖，直到數據報從遠端主機抵達為止。 當數據可用時， Receive 方法會讀取第一個加入佇列的數據報，並將數據部分傳回為位元組陣列。 這個方法會在 參數中填IPAddress入remoteEP發件者的和埠號碼。

如果您在方法中 Connect 指定預設遠端主機，此方法 Receive 將只接受來自該主機的數據報。 所有其他數據報都會被捨棄。

如果您收到 SocketException，請使用 SocketException.ErrorCode 來取得特定的錯誤碼。 取得此程式代碼之後，您可以參閱 Windows Sockets 第 2 版 API 錯誤碼 檔，以取得錯誤的詳細描述。

注意

如果您想要接收多播的數據報，請勿在呼叫 Receive 方法之前呼叫 Connect 方法。 UdpClient您必須使用多播埠號碼來建立您用來接收資料報的 。

另請參閱

• Send(Byte[], Int32, IPEndPoint)
• IPEndPoint
• Connect(String, Int32)
• IPAddress