Author: Tomas Rutkauskas

How can I prevent to open a MDIChild if it is already open? When I select the same 
option on the menu, the first code executes again and I get two forms.

Answer:
1   
2   procedure TformMain.doDisplayCustomerLookupGrid(Sender: TObject);
3   var
4     MyChildFormName: string;
5     MyChild: TformCustGrid;
6     I: Integer;
7   begin
8     MyChildFormName := 'Customer Lookup';
9     { If the child form already exists, make it active }
10    with formMain do
11      for I := 0 to MDIChildCount - 1 do
12      begin
13        if MDIChildren[I].Caption = MyChildFormName then
14        begin
15          MDIChildren[I].BringToFront;
16          exit;
17        end;
18      end;
19    { If the child form does not exist, create it }
20    MyChild := TformCustGrid.Create(Application);
21    MyChild.Caption := MyChildFormName;
22  end;