ReDim an Array Pointer VB6

Question

Hi guys,

I'm trying to ReDim a member object array from a different class. For example:

Class1.cls

Dim mStuffArray() As New clsStuff

Property Get StuffArray() As clsStuff()
    StuffArray = mStuffArray
End Property

Class2.cls

Private Sub Foo(ByRef pClass1 As Class1)
    Dim tStuffArray() As clsStuff

    tStuffArray = pClass1.StuffArray
    ReDim tStuffArray(1 To 2)
End Private

The problem here is that Foo doesn't seem to be ReDim'ing the member mStuffArray in Class1. Any idea what I'm doing wrong? Forgive me if my VB6 looks odd or the naming conventions aren't standard, I had to dive into some old legacy code and am new to VB6

Dave

Answer 1

I've never looked into VB6, but if I were to take a guess, I think when you use ReDim, it creates a copy of the existing Array and changes tStuffArray to point to the new copy. However, pClass1.mStuffArray still references the old array.

The documentation for ReDim states that "ReDim creates a new array, copying all the elements from the existing array"

I would recommend adding a method to to Class1 that performs ReDim on the private mStuffArray variable.

Dim mStuffArray() As New clsStuff

Property Get StuffArray() As clsStuff()
    StuffArray = mStuffArray
End Property

Sub Foo()
     ReDim mStuffArray(1 To 2)
End Sub

Hopefully this works. As I said, I'm not a VB6 programmer, so I may be off on this.

Answer 2

Redim doesn't make a copy of the array.

I think it's more likely that 4eturning the array from a property get creates a copy. The docs aren't very clear. http://msdn.microsoft.com/en-us/library/aa261343(VS.60).aspx

It would be simpler to use a Public member variable. And why not use a Collection rather than an array?

Answer 3

You might also want to consider the Dictionary object.