Declare class inside conditional statement?

[Andrew]

What's the best way to do this:

Dim bTrue As Boolean
If bTrue = True Then
Dim TheClass As New classA
Else
Dim TheClass As New classB
End If

TheClass.DoSub


The easy way I figured out was, but it doesn't seem as tight as the above
code (and VB.Net doesn't allow the above code):

Dim bTrue As Boolean
If bTrue = True Then
Dim TheClass As New classA
TheStructure.DoSub
Else
Dim TheClass As New classB
TheStructure.DoSub
End If

 

[Alex Clark]

How does the compiler know that DoSub exists on TheClass, if it doesn't know
for sure what type TheClass is?

You have a few options. First you can turn off Option Explicit in that
particular code file and use late binding - that would work.

Or you can declare an interface, IDoSub, and implement it on both classA and
classB (preferred).

Then your code would look something like:

Dim TheClass as IDoSub
Dim bTrue As Boolean

If bTrue = True Then
TheClass = New classA
Else
TheClass = New classB
End If

TheClass.DoSub

-Alex