About ServerSockets, TCPSockets and EventHandling

[Brian_O_Brien]

I have instantiated an instance of a MySS::ServerSocket on my MainWindow.
AddSocket instantiates a MyTCPSocket returns it as a TCPSocket
MyTCPSocket class declares an event MyDataReceived, which it ‘raises’ (?) after the TCPSocket dataAvailable event is done.

How do I receive the MyDataRecieved event on my MainWindow? Who got the event?

[Tim_Parnell]

On your MySS on MainWindow add an Event Handler.

You should see the MyDataReceived event if you defined it on the class and did not implement a handler for it elsewhere.

[Brian_O_Brien]

I simply do not have my ‘Message’ event as ‘addable’.

Function AddSocket() Handles AddSocket as TCPSocket
  
  Dim ret As MLLP_HL7SegmentFactory = New MLLP_HL7SegmentFactory(mCurrentSocket)  
  mCurrentSocket = mCurrentSocket + 1 
  Return TCPSocket(ret)
  
End Function

[Mike_D]

This may be off-topic, but how do you get the class name to show in the IDE like this?

[Brian_O_Brien]

I ‘edited’ the screen shot, 'cause like the IDE doesn’t do that… but it would be a nice feature, wouldn’t it?

[Jürg_Otter]

@Brian_O_Brien

I simply do not have my ‘Message’ event as ‘addable’.

Have a close look again at Tim’s ScreenShot - and then at the one of your project structure.

Assuming you would add an MLLP_HL7SegmentFactory to your MainWindow, you could then add the EventHandler Message to MLLP_HL7SegmentFactory1 there.

You obviously can’t add the EventHandler Message to your MLPServerSocket1 on your MainWindow, because your MLPServerSocket does not define a (custom/own) EventDefinition Message.

---

@Brian_O_Brien

I have instantiated an instance of a MySS::ServerSocket on my MainWindow.
AddSocket instantiates a MyTCPSocket returns it as a TCPSocket
MyTCPSocket class declares an event MyDataReceived, which it ‘raises’ (?) after the TCPSocket dataAvailable event is done.

How do I receive the MyDataRecieved event on my MainWindow? Who got the event?

Uff, a bit too tricky to explain in plain text. And different approaches that would be possible.

One possible way:

• Start by adding EventDefinition Message to your MLLPServerSocket
• When instantiating your MLLP_HL7SegmentFactory TCPSocket’s in there
  • AddHandler to receive their Message’s
  • likely you then want to forward their received messages by RaiseEvent Message

So the original Message is created in TCPSocket → listened by ServerSocket → forwarded to EventDefinition on ServerSocket → which can be added as an EventHandler on the Instance of your ServerSocket in your MainWindow to get the messages there.

[Jürg_Otter]

@Jürg_Otter

And different approaches that would be possible

I’d prefer to use a Delegate here…

…anyway - here are two ways how to get a “Message” from TCPSocket → TCPServer → Window.

• using Event
• using Delegate

ServerSocketMessage.zip (524.2 KB)

Note: Code is quick&dirty, just to show the two mentioned approaches. Both could obviously be improved or done differently. The goal was really just to show the “flow” how a “Message” could go from TCPSocket to Window.

Run the example and click on the two Buttons (which opens the Browser at the listened ports, Sockets are writing a silly simple text to the browser).
And I hope the example shows how “Messages” in the TCPSockets are finally showing up on the Main Window.

@Brian_O_Brien

How do I receive the MyDataRecieved event on my MainWindow? Who got the event?

I hope this example helps to understand what I’ve tried to write in the previous answer…