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Reading the state of mouse buttons within DO WHILE loop

Before you begin:

See also:

• Capturing keyboard activity of another application using the Raw Input API

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Code:

DECLARE INTEGER GetAsyncKeyState IN user32 INTEGER vKey
DECLARE INTEGER GetKeyState IN user32 INTEGER vKey
DECLARE INTEGER SetKeyboardState IN user32 STRING @lpKeyState

#DEFINE VK_LBUTTON  1
#DEFINE VK_RBUTTON  2

LOCAL cBuffer, nIndex, lStop
lStop=.F.

* clearing input-state table
cBuffer = REPLICATE(CHR(0), 256)
= SetKeyboardState(@cBuffer)
DOEVENTS

DO WHILE Not lStop
	* simulating time-consuming activity
	CREATE CURSOR cs (num N(10))
	FOR nIndex=1 TO 1000
		INSERT INTO cs VALUES (nIndex)
	ENDFOR

	?? "."
*	DOEVENTS

	* testing if any mouse key has been pressed
	* since previous call to this function
	IF GetKeyState(VK_LBUTTON) <> 0
		? "Left button pressed."
		EXIT
	ENDIF

	IF GetKeyState(VK_RBUTTON) <> 0
		? "Right button pressed."
		EXIT
	ENDIF
ENDDO  

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Listed functions:

GetAsyncKeyState
GetKeyState
SetKeyboardState

Comment:

Check list of Virtual-Key Codes on the MSDN.

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