Question

I am doing support on a VB.Net application although I am primarily a C# developer. I have encountered what I consider to be “strange” code, in that my C# mindset tells me that the code is wrong and shouldn’t compile, yet it does. I did a Find all references on a particular form to see where it was being used and found references to the form where non-shred methods of the class were being directly referenced without the class being instantiated. In other words, I see code like this:

FrmCareer.ShowDialog(careerId)
FrmCareer = Nothing

Now ShowDialog is not a shared member, and it references instance member variables, so I would not expect intellisense to list the ShowDialog method at all. But it does and it compiles. Can anyone explain what is going on here?

Answer 1

VB.NET has the (very nice) feature of keeping a collection of all forms as properties under the My.Forms object. The objects there are instantiated when you first access them. In this way, you get a default instance of each form that you can refer to.

On the not so nice side, VB insists on importing the My.Forms object’s properties globally, and there’s nothing you can do to change that.

In other words, the class name of any form in your application doubles as a global instance of that form.