It's the MouseUp() that needs the code.

LPARAMETERS nButton, nShift, nXCoord, nYCoord
IF This.ReadOnly
NODEFAULT && This prevents the buffer from getting dirty when this control is ReadOnly.
ENDIF

>>>>You can also NODEFAULT in the MouseDown()
>>>
>>>Do I need to call DODEFAULT otherwise? It does prevent the click, but doesn't seem to allow it if condition met.
>>
>>

>>If (I do not want the click to happen )
>>   NODEFAULT
>>  return
>>endif
>>

>
>Doesn't work.
>
>It prevents the click even if I want it to happen.