Subject Re: key or Onkey event From Mervyn Bick <invalid@invalid.invalid> Date Sun, 24 Sep 2023 12:43:53 +0200 Newsgroups dbase.getting-started On 2023/09/23 22:16, Mustansir Ghor wrote: > Dear Heinz > > I am Entering a Value in Combobox and wish to force Action with Tab Key.  But when I press Enter Key It triggers Change event first so the condition for key event to look for Tab key only does not work. > It used to be common practice to use a combobox's onChange event handler to execute code depending on the selection made.  This has its problems as the event fires every time the user uses the arrow keys to move through the dropdown list.  Eventually dBASE added the onChangeCommitted event to address this. It's not a problem if the user only uses the mouse to make a selection in the combobox dropdown list but a combobox's onChange event fires every time a new value is highlighted in the dropdown list.  In other words, if the user uses the up and down arrows to move through the list, the onChange event fires each time a new value is highlighted.  If the user presses Enter then the onChangeCommitted event fires.  This has made the programmer's life much simpler. The combobox's key and onKey events do not fire when the up and down arrows are used. Except when the list contains only single character entries, when any other key is pressed (including the Backspace nChar = 8, Tab nChar = 9  and Enter nChar = 13) the key event fires followed by the onKey event. The key event fires before a character is passed on the dBASE.  It is, therefore, possible to use the key event handler to "swallow" keystrokes that one doesn't want the combobox to see.  To disable the Backspace key     function COMBOBOX1_key(nChar, nPosition,bShift,bControl)        local lRet        if nChar = 8 //Backspace          lRet = false        else          lRet = true        endif        return lRet Although it is normal to use either the onChange or the onChangeCommitted event handler to implement the user's selection in the combobox you don't have to use either of these two events at all.  You could just as easily use the onKey event handler instead.    function COMBOBOX1_onKey(nChar, nPosition,bShift,bControl)       if nChar = 9 //Tab         if this.value = 'Some'            //Appropriate code         elseif this.value = 'Thing'            //Appropriate code         elseif this.value = 'Else'            //Appropriate code         endif       endif       return Mervyn.