Error when simconnect is disposed

[Nabeel]

Hello,

 

Seeing this error from some clients:

Quote

V:0728 14:18:03 Disposing SimConnect client
E:0728 14:18:03 UnhandledException: UncaughtException::System.NullReferenceException
System.NullReferenceException: Object reference not set to an instance of an object.
   at FSUIPC.MSFSVariableServices.receiveValuesCallback(String name, Double value)
   at FSUIPC.WAPI.fsuipcw_getLvarValues(ReceiveValuesCallback ReceiveFunction)
   at FSUIPC.MSFSVariableServices.refreshData()
   at FSUIPC.MSFSVariableServices.lvarsValueChanged(IntPtr id, IntPtr Value)

V:0728 14:18:03 Disposal completed, marked for gc
I:0728 14:18:03 Sim client disconnected

This is my (shortened) shutdown code, but I'm sometimes seeing this error (pulling from crash logs)

if (VS.IsRunning) {
  VS.Stop();
}

// Remove the handler
if (callbackAdded) {
  Log.Verbose("Removing callbacks");
  VS.OnValuesChanged -= VS_OnValuesChanged;
  VS.OnLogEntryReceived -= VS_OnLogEntryReceived;
  callbackAdded = false;
}

try {
  Log.Verbose("Disposing SimConnect client");
  _simconnect?.Dispose();

  Log.Verbose("Disposal completed, marked for gc");
  _simconnect = null;
} catch (COMException) {
  // ignore - sim already said bye bye
}

 

[Paul Henty]

I've had a look - The Stop() method wasn't entirely thread-safe, so that might be causing this issue.

I've fixed this in 3.3.17-beta, now on Nuget. (Tick the box that says "Show Pre-Release").

Let me know if it's still a problem and I'll look into it some more.

Paul