It is possible to limit the users ability to type into an enterable object such as a field or variable. This is done using the FILTER KEYSTROKE during the On Before Keystroke Form event. To implement this, turn the On Before Keystroke Form event on for the object and paste this code into the objects form method.

If (Form event=On Before Keystroke)
  FILTER KEYSTROKE("")
End if

Note: It is not possible to capture the users actions related to the edit menu. The result is that the user can Cut, Paste into or Clear the contents of the field or variable without a corresponding form event occurring.