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Getting VK_SCROLL state in WinME

Posted on 2002-03-06
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Last Modified: 2013-12-03
I have a non-window app that keeps checking Scroll lock state every second. I use GetKeyState(VK_SCROLL) in WindowsXP and it returns 1 if scroll lock is on. But in WinME, GetKeyState only works if the dialog of my app got the focus. I changed to GetAsyncKeyState but it only reports the state (pushed or released), not on/off of the toggle button.
How would I know the state (on/off) of scroll lock?
daitt
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Question by:daitt
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by:cookre
ID: 6846231
Have you tried GetKeyboardState() to see if it has a similar undesirable behavior under ME?
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by:daitt
ID: 6846256
I don't have winME here to test, but yesterday I tested it and GetKeyboardState() didn't return the on/off state (as I remember it returns the same result as GetKeyState).
I don't want to use hooks because my program is very small I want it to be an alone exe file (use hook I will need a dll file).
It's hard to believe that such a simple task is impossible.
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cookre earned 50 total points
ID: 6846363
Alas, it would appear to be so.  You may also have found:

http://www.delphifaq.com/fq/q2050.shtml

part of which states:

GetKeyState and GetAsyncKeyState only work with Win95, Win98, NT4, Terminal Server and Windows 2000. But on WinME it always returns zero. These two functions are simply skipped by Millenium Edition!

Official explanation from Microsoft:

Intentionally disabled.
It didn't work all that well on some newer hardware, and worked less well with the passage of time, so it was fully disabled in ME.

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by:daitt
ID: 6846574
Thanks for the info. Microsoft document made me crazy for a while (it doesn't mention about that anywhere in my MSDN).
Now I scan keystate of VK_SCROLL all the time and calculate the state myself. The timer interval I set tok 10ms. It works ok now :)
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