>>* MouseDown
>>LPARAMETERS nButton, nShift, nXCoord, nYCoord
>>
>>* Top and Left of the button relative to the form
>>* If button is placed directly on the form, this step is not necessary
>>lnTop  = OBJTOCLIENT(This, 1)
>>lnLeft = OBJTOCLIENT(This, 2)
>>
>>* X and Y coordinates of the mouse relative to the button
>>lnX = nXCoord - lnLeft + 1
>>lnY = nYCoord - lnTop + 1
>>* ...
>>