Calling the same function on eterogene MdiChild FormVB.NET

Question

I have a list of eterogene MDIChildForms (MyChild1, MyChild2, ...) in my MDIParent. All of this form have a public function myFunction(p As myType). I would like to loop them and for each one call myFunction.

Pseudocode:

For Each myChild In Me.MdiChildren
     myChild.myFuntion(p)
Next

Is it possible? How can I do that? Thanks

Answer 1

You should define an interface that declares that method and then implement that interface in each child form class.

Public Interface ISomeInterface

    Sub SomeMethod()

End Interface

Public Class Form1
    Implements ISomeInterface

    Public Sub SomeMethod() Implements ISomeInterface.SomeMethod
        '...
    End Sub

End Class

You can then cast each form as that type and call the method, e.g.

For Each mdiChild As ISomeInterface In MdiChildren
    mdiChild.SomeMethod()
Next

That assumes that every form implements that interface. If some don't, you can do this:

For Each mdiChild In MdiChildren.OfType(Of ISomeInterface)()
    mdiChild.SomeMethod()
Next