Shawn,

Thanks for your replies.

Your snippet is working fine. I just found out that a Select-Case-EndSelect is working fine as long as I don't try to do something with another control.

This works just fine:
 Code:
Function cmb_ST_TextChanged($sender,$e)
Select
   Case $sender.Text = "Daily"
        ? 'Daily'
   Case $sender.Text = "Weekly"
        ? 'Weekly'
   Case $sender.Text = "Monthly"
        ? 'Monthly'
EndSelect
EndFunction


This will fail:

 Code:
Function cmb_ST_TextChanged($sender,$e)
Select
   Case $sender.Text = "Daily"
	$GroupBoxDaily.Visible = 1
	$GroupBoxWeekly.Visible = 0
	$GroupBoxMonthly.Visible = 0
   Case $sender.Text = "Weekly"
	$GroupBoxDaily.Visible = 0
	$GroupBoxWeekly.Visible = 1
	$GroupBoxMonthly.Visible = 0
   Case $sender.Text = "Monthly"
	$GroupBoxDaily.Visible = 0
	$GroupBoxWeekly.Visible = 0
	$GroupBoxMonthly.Visible = 1
EndSelect
EndFunction


After some testing, this is failing to:

 Code:
Function cmb_ST_TextChanged($sender,$e)
Select
   Case $sender.Text = "Daily"
	$Button1.Visible = 1
   Case $sender.Text = "Weekly"
	$Button2.Visible = 1
   Case $sender.Text = "Monthly"
	$Button1.Visible = 0
	$Button2.Visible = 0
EndSelect
EndFunction


The Select-Case-EndSelect statement does seem to be able to handle any action to controls.
When I put the $Button1.Visible = 0 after the EndSelect, $Button1 is gone after I've changed the value of the Combobox.
So within the eventhandler cmb_ST_TextChanged I can do various actions towards controls, as long
as they are not performed after a Case.

This works fine:

 Code:
Function cmb_ST_TextChanged($sender,$e)
Select
   Case $sender.Text = "Daily"
	? 'Daily'
   Case $sender.Text = "Weekly"
	? 'Weekly'
   Case $sender.Text = "Monthly"
	? 'Monthly'
EndSelect

$ButtonScheduleJobClose.Visible = 0
EndFunction