A control based on UserControl does have a load event, is your control
based on UserControl or another type of control?

mamil@bezeqint.net wrote: >> Problem is - I can't find that event for user
controls !

You could create a UserControl, then, in its load event, create an instance of
your over-ridden combobox, set its dockstyle to 'fill.

In a similar situation (a compound control inheriting from Label) I used the
following code to make sure I called the code that built the run-time "ui" only
when in run-time mode : whether this can be adapted to function in exactly the
way you want ?

 // Override 'CreateControl to avoid design-time errors :
 // build the UI only when we are NOT in design mode
 protected override void OnCreateControl()
 {
      base.OnCreateControl();
      if(this.Site == null)
      {
           CreateUI();
     }
 }

best, Bill Woodruff
dotScience
Chiang Mai, Thailand