⤷ Limit the count of MDIChild form

The count of the MDIChild forms can be looked in the MDIChildCount property. In this example you can open 10 MDIChild forms only.
Don't forget to remove line
Application.CreateForm(TForm2, Form2) from project file and line
var Form2: TForm2 from unit2.pas file.

procedure TForm1.New1Click(Sender: TObject);
var
  ChildForm: TForm2;
begin
  if MDIChildCount<10 then
  begin
    ChildForm:=TForm2.Create(Application);
    ChildForm.Caption:='Child - '+IntToStr(MDIChildCount);
  end;
end;
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