Understanding Delegates & Callbacks

Question

Using this C# TCP Server example within a Unity project

https://www.codeproject.com/articles/488668/csharp-tcp-server

The notes mention There are 3 callback events OnConnect, OnDataAvailable and OnError. There are 2 callback examples with the following signatures

private void tcpServer1_OnDataAvailable(tcpServer.TcpServerConnection connection)

Do I need to do anything special or in addition to enable these callbacks or is tcpServer1_OnDataAvailable consdiered a reserved handler name that is automatically called?

TcpServer tcpServer1 = new TcpServer(); //in constructor (auto added if added as a component)

private void openTcpPort(int port)
{ 
    tcpServer1.Port = port;
    tcpServer1.Open();
}

private void closeTcpPort()
{
    tcpServer1.Close();
}  

Answer 1

You'll need to register the event handlers delegates to the specific events.

TcpServer tcpServer1 = new TcpServer(); 

// register event handler
tcpServer1.OnDataAvailable += tcpServer1_OnDataAvailable;


private void tcpServer1_OnDataAvailable(tcpServer.TcpServerConnection connection)
{
  // do work
}

Answer 2

Callbacks are methods that are called when an event you are interested in occurs. You do in fact need to set them up, like this:

tcpServer1.OnConnect += serverConnection => 
{
   //code to do stuff when a connection happens goes here
}

tcpServer1.OnDataAvailable += serverConnection =>
{
  //code to do stuff when data is available here
}

tcpServer1.OnError += serverConnection => 
{
   //code to do stuff when an error happens here
}

You should put this code in the constructor, after the point in time when tcpServer1's variable is instantiated with operator new.