Question

I have some C# code I’m trying to convert to VB.NET. There are some external dependencies I’m referencing in each project. The C# line is

TWriteFileCommand writeFile = (TWriteFileCommand)CommunicationLink.CreateCommand(TOPKernel.TCommand.CommandType.WriteFile); 

I don’t really understand what the TWriteFileCommand in parathesis after the equal sign is for in that statement. When I try to do it in VB.NET, I keep getting errors because I can’t get a reference to the CreateCommand function. The closest I’ve gotten is this:

Dim MyAppBase As OPSupport.App.AppBase Dim writeFile As TWriteFileCommand writeFile = MyAppBase.CommunicationLink.CreateCommand(TOPKernel.TCommand.CommandType.WriteFile) 

However, I have a green underline after the equal sign @ MyAppBase that flags an error ‘Variable MyAppBase is used before it has been assigned a value. A null reference exception could result at runtime.’

What am I missing? Why in the C# code is the instance fine and what do I need to get the equivalent instance in VB.NET? Please advise.

Answer 1

The direct equivalent is:

Dim writeFile As TWriteFileCommand  writeFile = DirectCast(CommunicationLink.CreateCommand(TOPKernel.TCommand.CommandType.WriteFile), TWriteFileCommand)