Global $var = 0
GUICreate("Form1", 277, 186, 192, 124)
$Button1 = GUICtrlCreateButton("Start", 104, 136, 75, 25)
$Label1 = GUICtrlCreateLabel("00", 112, 40, 100, 60)
GUICtrlSetFont(-1, 36, 800, 0, "Arial")
GUISetState()
AdlibRegister('_Timer', 100)
While 1
$nMsg = GUIGetMsg()
Switch $nMsg
Case -3
Exit
Case $Button1
If $var = 0 Then
$var = 1
GUICtrlSetData($Button1, 'Stop')
Else
$var = 0
GUICtrlSetData($Button1, 'Start')
EndIf
EndSwitch
WEnd
Func _Timer()
If $var = 1 Then GUICtrlSetData($Label1, GUICtrlRead($Label1) + 1)
EndFunc