static/Shared in VB.NET and C# visibility

Question

I have faced with a situation in VB.NET and C# (.NET2) with the visibility of the static/shared members. It seems to me a little strange in VB.NET:

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Answer 1

It's not an oversight but your VB code will trigger a warning, which plainly means: do not use this notation.

In VB, static members can be accessed via an instance, since strictly speaking, VB doesn’t have static: VB has the keyword Shared, meaning that the member is shared between all instances, as opposed to static where a member doesn’t belong to any instance.

Now, this is a semantical distinction between those keywords. It just so happens that these two distinct semantics tend to have the exact same effect.

Of course, static in C# is today identical to Shared in VB.NET but their legacy is different and VB’s Shared simply has a different history and therefore historically a different meaning. With this meaning, it makes absolutely sense to access Shared members via an instance.

It also makes sense when used together with Option Strict Off (loose typing): here, you sometimes don’t know a variable’s type but you still might want to access a Shared member. Now, you’ve got no choice but to use an instance to access it:

Option Strict Off
' … '
Dim o As Object = New A()
' Somewhere else, we want to access a static member of A but we don’t know A: '
Dim instance = o.Instance