How do I check for an object being Nothing in VB6?

Question

In my VB6 application I have an array of objects declared thus...

Dim MyArray() as MyClass

This array is filled in as processing goes on

Set MyArray(element) = passed_object

and as elements are no longer wanted,

Set MyArray(otherelement) = Nothing

When using the array, I want to use a loop like

For i = 1 To Ubound(MyArray)
    If MyArray(i) <> Nothing Then    ' Doesn't compile
        ...do something...
    End If
Next i

But I can't get anything likely-looking to compile. I've also tried

If MyArray(i) Is Not Nothing Then

Should I want to do this, and if so, what test should I put in here?

VB has an `IsNot` operator, so just remove a space to get `If MyArray(i) IsNot Nothing Then`... there is usually a preference for this syntax over `Not... Is Nothing` — u8it, Jan 22 '16 at 16:10
@u8it, VB6 does not have an IsNot operator. That appeared only in VB.Net. — Luc VdV, Sep 10 '18 at 10:11

score 39 · Accepted Answer · answered Mar 17 '11 at 15:06

39

If Not MyArray(i) Is Nothing Then

answered Mar 17 '11 at 15:06

mwolfe02

score 15 · Answer 2 · answered Mar 17 '11 at 15:06

15

If Not MyArray(i) Is Nothing Then

answered Mar 17 '11 at 15:06

AakashM

score 0 · Answer 3 · answered Oct 16 '13 at 08:37

0

Instead of

IsNothing(<object here>)

this should work in VB6:

<object here> Is Nothing

answered Oct 16 '13 at 08:37

user2885606

add some explanations also – SpringLearner Oct 16 '13 at 08:56
Yes, that's what all the other answers say. They've been here for over two years. Sorry, but your answer doesn't add anything. – MarkJ Oct 16 '13 at 12:02

score 0 · Answer 4 · answered Jan 29 '14 at 15:33

0

    Private Function IsNothing(objParm As Object) As Boolean
        IsNothing = IIf(objParm Is Nothing, True, False)
    End Function

answered Jan 29 '14 at 15:33

Chris Catignani

5

Or a bit more succinctly, `IsNothing = objParam Is Nothing`. – Gregory Higley Oct 20 '14 at 18:19

4 Answers4