Implementing my own interface in vba always raise this error !!!

Question

how to Implements my class 'ClsInterface' which have this code

Public Function add(x As Integer, y As Integer) As Integer
End Function

in my class 'Class2' which have this code

Implements ClsInterface

Public Function add(x As Integer, y As Integer) As Integer
add = x + y
End Function

my test code is

Public Sub test()
Dim obj As New Class2
MsgBox obj.add(5, 2)
End Sub

so it's always comes up with the following error:

---

Microsoft Visual Basic

Compile error:

Object module needs to implement 'add' for interface 'ClsInterface'

OK Help

and no help is there on Microsoft help ? (when I pressed on Help button)

any Idea?

million thanks in all cases :)

Answer 1

Your Class2 must look like;

Implements ClsInterface

Private Function ClsInterface_add(x As Integer, y As Integer) As Integer
add = x + y
End Function

(Checkout the drop-down boxes at the top of Class2's code window, you can see what base object you can refer to; Class or ClsInterface)

In your test code you want;

Dim obj As New ClsInterface

If you want to call across the interface.

(I would also recommend naming intefaces in the form ISomeDescription and using Set rather than As New)