Notes

; --- simple example of use ---
#include <GUIConstantsEx.au3>
$Form1_1 = GUICreate("Stopwatch", 170, 70);, 100, 100)
$LapsedTime = GUICtrlCreateLabel(" 00:00:00.0", 10, 10, 200, 25)
GUICtrlSetTip(-1, "Lapsed time")
GUICtrlSetFont(-1, 18)
$Button1 = GUICtrlCreateButton("halt/go", 10, 40, 50, 20) ; go / pause
GUICtrlSetTip(-1, "Pause/Unpause counting")
$Button2 = GUICtrlCreateButton("clear", 60, 40, 50, 20) ; reset
GUICtrlSetTip(-1, "Clears counter and stops")
$Button3 = GUICtrlCreateButton("restart", 110, 40, 50, 20) ; restart
GUICtrlSetTip(-1, "Clears counter and restarts")
GUISetState(@SW_SHOW)

Stopwatch(2) ; reset to 0 and stops
While 1
$x = Int(Stopwatch() / 100)
$nMsg = GUIGetMsg()
Switch $nMsg
Case $GUI_EVENT_CLOSE
Exit
Case $Button1 ; toggle status (go <-> pause)
Stopwatch() ; this reads counter and sets @extended according to actual $paused status
Stopwatch(@extended) ; if is paused (@extended = 1) then unpause [Stopwatch(1)]
; if is unpaused (@extended = 0) then pause [Stopwatch(0)]
Case $Button2 ; reset to 0 and stop counter
Stopwatch(2)
Case $Button3 ; reset to 0 and restart counter
Stopwatch(3)
EndSwitch

If $x <> Int(Stopwatch() / 100) Then
$totsec = Int(Stopwatch() / 1000) ; ms to sec
$hr = Int($totsec / 3600) ; hours
$mn = Int(($totsec - ($hr * 3600)) / 60) ; minutes
$sc = Int(($totsec - ($hr * 3600) - ($mn * 60))) ; seconds
$tn = Int((Int(Stopwatch() / 100) - ($hr * 36000) - ($mn * 600) - ($sc * 10))) ; tenths of a second
GUICtrlSetData($LapsedTime, " " & StringFormat("%02s", $hr) & ":" & StringFormat("%02s", $mn) & ":" & StringFormat("%02s", $sc) & "." & StringFormat("%01s", $tn))
EndIf
WEnd
; --- end of example ---

; #FUNCTION# (snippet) ==========================================================================================================
; Name...........: Stopwatch
; Description ...: returns the number of milliseconds counted (according to actions requests by caller)
; Syntax.........: Stopwatch([$action])
; Parameters ....: $action: 0 - pause counting
; 1 - resume counting
; 2 - reset counter to 0 and stops
; 3 - reset counter to 0 and start counting
; 4 - (default) just ruturns actual counting value and status (status in @extended)
;
; Return values .: number of milliseconds in counter
; @extended contains paused status (1 or 0)
; 1 if stopwatch is in pause
; 0 if stopwatch is counting
;
; Author ........:
; Modified.......:
; Remarks .......:
; Related .......:
; Link ..........:
; Example .......: yes
; ===============================================================================================================================

Func Stopwatch($ToggleTo = 4)
Static Local $Paused = True
Static Local $Stopwatch = 0
Static Local $TotalTime = 0
Switch $ToggleTo
Case 0 ; pause counter
If $Paused Then
SetExtended($Paused) ; $Paused status
Return $TotalTime ; already paused, just return current $TotalTime
Else
$TotalTime += TimerDiff($Stopwatch)
$Paused = True
SetExtended($Paused)
Return $TotalTime
EndIf
Case 1 ; unpause counter
If $Paused Then
$Stopwatch = TimerInit()
$Paused = False
SetExtended($Paused)
Return $TotalTime
Else
SetExtended($Paused)
Return $TotalTime + TimerDiff($Stopwatch)
EndIf
Case 2 ; reset to 0 and pause
$Paused = True
$TotalTime = 0
SetExtended($Paused)
Return $TotalTime
Case 3 ; reset to 0 and restart
$Paused = False
$TotalTime = 0
$Stopwatch = TimerInit()
SetExtended($Paused)
Return $TotalTime
Case 4 ; return status
SetExtended($Paused)
If $Paused Then
Return $TotalTime
Else
Return $TotalTime + TimerDiff($Stopwatch)
EndIf
EndSwitch
EndFunc ;==>Stopwatch