Help returning NULL objects from VB6 Property

[atconway]

Ok I lived VB6 long ago, but am making an enhancment to a legacy VB6 app. The problem is I don't have the syntax quite right for returning objects from a class property that have no value.

In .NET this is trival, as returning the backing variable value and then having the caller check to see if it 'Is Nothing' works. In VB6 there (obviously) is no Return statement on Properties and the actual Return is assignment onto itself and I think this is where I am running into issues. The error I get is the famous "Object variable or With block varibale not set". So let me give the code example. This property referencing 'MyClass2' is within another class named MyClass1.

Private _mc2 As New MyClass2
 
Public Property Get mc2() A MyClass2
   'This is where it bombs with the error mentioned above when checking if
   'the value Is Nothing from the calling code
   mc2 = _mc2
End Property
 
Public Property Let mc2(ByVal Value As MyClass1)
   _mc2 = Value
End Property

Here would be an example calling code that causes the above to error:

'Say an intance of MyClass1 which contains the instance property. Assuming the mc2 Property has NO value (Is Nothing = True), I am going to test it like below:

Dim mc1 As New MyClass1
If mc1.mc2 Is Nothing Then
 
End If

Any ideas on how I can test for a Property on a class that is actually an instance of a property, and check if it Is Nothing without getting the error?

Thanks!

[westconn1]

if isnull(var) then

[atconway]

Nevermind I figured this out.... I always forget to use the 'SET' statement when assigning objects in VB6. So the property needed to look like this:

Public Property Get mc2() A MyClass2
   'Works
   Set mc2 = _mc2
End Property

[si_the_geek]

As you now have it sorted out, could you please do us a little favour, and mark the thread as Resolved?
(this saves time reading for those of us who like to answer questions, and also helps those who search to find answers)

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