UdpClient.Receive(IPEndPoint) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
回傳由遠端主機傳送的 UDP 資料報。
public:
cli::array <System::Byte> ^ Receive(System::Net::IPEndPoint ^ % remoteEP);
public byte[] Receive(ref 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
a IPEndPoint 代表資料傳送的遠端主機。
傳回
一個包含資料報資料的陣 Byte 列。
例外狀況
標的 Socket 資產已經關閉。
存取該套接字時發生錯誤。
範例
以下範例示範此 Receive 方法。 該 Receive 方法會阻擋執行,直到收到訊息。 利用 IPEndPoint 傳遞到 Receive的 ,會揭示回應主機的身份。
//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
此 Receive 方法會阻塞,直到遠端主機收到資料報。 當資料可用時,方法 Receive 會讀取第一個佇列的資料報,並將資料部分以位元組陣列的形式回傳。 此方法會 remoteEP 將參數填入 IPAddress 發送端的 和 埠號。
如果你在方法中 Connect 指定預設的遠端主機,該 Receive 方法只會接受該主機的資料報。 其他資料報都會被丟棄。
如果您收到 SocketException,請使用 SocketException.ErrorCode 以取得特定的錯誤代碼。 取得這些程式碼後,你可以參考 Windows Sockets 版本 2 的 API 錯誤程式碼 文件,了解錯誤的詳細說明。