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socketsudpasyncsocket

Extract IP from IAsyncResult UDP

I want to extract IP address from an object of IAsyncResult UDP in EndReceive Method (IAsyncResult ar)

If it's possible, How can I do that?

Here the code:

public void End_Receive(IAsyncResult ir)
{
        //Here I need the sender IP
        ServerSocket.EndReceive(ir);
        ReceivedMessage =  System.Text.UnicodeEncoding.Unicode.GetString(buffer);
}
Solution

  • If you are using TCP, or connected UDP, use the Socket.LocalEndPoint and Socket.RemoteEndPoint properties.

    If you are using connection-less UDP, you should be using Begin/EndReceiveFrom() instead of Begin/EndReceive(). The callback provides an EndPoint for the sender.

    Either way, given an EndPoint object, cast it to an IPEndPoint and use its Address property to access the IP address.