Binaryworld - Showing and enumerating MDI child forms ... [ VB.net -> WinForms ]

An MDI child form is a regular form whose MdiParent property points to its MDI container form, so the code that creates and displays a child window is very simple:

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Sub ShowMdiChildWindow()
  ' Display the MenuForm form as a child of this form.
  Dim frm As New MenuForm()
  ' Make it a child of this MDI form before showing it.
  frm.MdiParent = Me
  frm.Show()
End Sub

A form that can be used either as a regular form or an MDI child form might need to determine how it's being used. It can do that by testing its MdiParent property or its read-only IsMdiChild property. You can list all the child forms of an MDI parent by using the Form array returned by its MdiChildren property:

Click here to copy the following block

Dim frm As Form
For Each frm In Me.MdiChildren
Debug.Write(frm.Text)
Next