C# to VB conversion query

Question

This C# code successfully gets the 2 relevant records into _currentUserRegisteredEventIds:

ctx.FetchEventsForWhichCurrentUserIsRegistered((op) =>
            {
                if (!op.HasError)
                {
                    var items = op.Value;
                    _currentUserRegisteredEventIds = new HashSet<int>(items);
                    UpdateRegistrationButtons();
                }
            }, null);

but VB code trying to do the same thing has nothing in _currentUserRegisteredEventIds:

ctx.FetchEventsForWhichCurrentUserIsRegistered(Function(op)
     If Not op.HasError Then
          Dim items = op.Value
          _currentUserRegisteredEventIds = New HashSet(Of Integer)(items)
          UpdateRegistrationButtons()
          End If
          End Function, Nothing)
        Else
            _currentUserRegisteredEventIds = Nothing
            UpdateRegistrationButtons()
        End If   

Any help appreciated.

Answer 1

Where's the second parameter for FetchEventsForWhichCurrentUserIsRegistered in the VB example? Are you calling a different overload?

Answer 2

You are missing the null / Nothing in the vb code

Answer 3

I'm not sure if your code is formatted exactly as you have it printed here. I would think what you have above would not compile. See comments in code below:

ctx.FetchEventsForWhichCurrentUserIsRegistered(Function(op) 
     If Not op.HasError Then 
          Dim items = op.Value 
          _currentUserRegisteredEventIds = New HashSet(Of Integer)(items) 
          UpdateRegistrationButtons() 
          End If  ' End if of the main conditional
          End Function, Nothing)  ' End of the function
        Else   ' What is this else doing here? It seems to be orphaned
            _currentUserRegisteredEventIds = Nothing 
            UpdateRegistrationButtons() 
        End If 

I would think it would need to look a little more like:

ctx.FetchEventsForWhichCurrentUserIsRegistered(Function(op) 
     If Not op.HasError Then 
          Dim items = op.Value 
          _currentUserRegisteredEventIds = New HashSet(Of Integer)(items) 
          UpdateRegistrationButtons() 

        Else 
            _currentUserRegisteredEventIds = Nothing 
            UpdateRegistrationButtons() 
        End If
    End Function, Nothing)