Try using a generic method:
Private Sub CreateChild(Of TForm As {Form, New})()
Dim frmChild As New TForm()
...
End Sub
To call it, you need to specify the type of form you want to create:
CreateChild(Of YourCustomForm)()
The type must inherit from
Form
, and must have a public parameterless constructor.
Generic Types in Visual Basic (Visual Basic) | Microsoft Docs[
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