Cannot declare a variable with public access in a class from a module

Question

I am making a GUI based application (forms), and encountered the following error.

Firstly, I am declaring the following stuff in a module

Module test_mod         


        

Answer 1

By default modules and classes are Friend (only visible to your assembly).

Your form, however, is explicitly Public, which exposes it and its members to the world - which extends test_mod.main_struct's visibility.

Declare your module as Public too.

Answer 2

Try this:

Public Module test_mod
    Public Structure sub_struct
        Public test_int() As Integer

        Public Sub foo()
            ReDim test_int(3)
        End Sub
    End Structure

    Public Structure main_struct
        Public test_aaa As sub_struct
    End Structure
End Module

Source: http://msdn.microsoft.com/en-us/library/aaxss7da.aspx