Don't let INKEY$ byte you in the ASCII

Don't let INKEY$ byte you in the ASCII - Printable Version

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Don't let INKEY$ byte you in the ASCII - Pete - 02-01-2026

I mostly love INKEY$, but we can't rely on it to accurately report a key was not released. So here are some observations. The last example is a Combined Inkey$ and _Keyhit solution.

Hold down the "A" key and don't release it. See, INKEY$ says it was released!

Code: (Select All)

Do

    _Limit 30

    b$ = InKey$

    If Len(b$) Then

        If a$ <> b$ Then a$ = b$: Print a$ + " was pressed."

    Else

        If Len(a$) Then Print a$ + " was released.": a$ = ""

    End If

Loop

Now a jerkaround is to add a delay. This works, but sucks...

Code: (Select All)

Do

    _Limit 30

    b$ = InKey$

    If Len(b$) Then

        If a$ <> b$ Then a$ = b$: Print a$ + " was pressed.": _Delay .5

    Else

        If Len(a$) Then Print a$ + " was released.": a$ = ""

    End If

Loop

That's right. At least in my system anything less than a half-second delay fails! Imagine typing with a half-second delay.

So to ease the delay situation, we create a mock buffer and time it. (This is what I had to do before QB64).

Code: (Select All)

Do

    _Limit 30

    b$ = InKey$

    If Len(b$) Then

        If a$(cnt) <> b$ Then cnt = cnt + 1: a$(cnt) = b$: Print a$(cnt) + " was pressed.": z1 = Timer

    Else

        If Len(a$(cnt)) And Abs(z1 - Timer) > .49 Then

            Print a$(cnt) + " was released.": a$(cnt) = "": cnt = cnt - 1

        End If

    End If

Loop

I know, I know. I didn't bother to dim the array (buffer), so it will fail after 10 here, and I didn't bother to do a complete 24-hour timer, so it would fail once at mid-night, but I'm keeping it as simple coded as possible for this discussion.

Anyway, all this crap can be avoided using the _KeyHit method or by adding _KeyHit to the Inkey$ routine.

_KeyHit Method

Code: (Select All)

Do

    _Limit 30

    k = _KeyHit

    If k > 0 Then

        If j <> k Then j = k: Print j; "was pressed."

    ElseIf k < 0 Then

        If j Then Print j; "was released.": j = 0

    End If

Loop

And finally, our combined INKEY$ with _KEYHIT solution...

_KeyHit used with Inkey$ Method

Code: (Select All)

Do

    _Limit 30

    b$ = InKey$

    k = _KeyHit

    If k < 0 Then Print a$ + " was released.": a$ = ""

    If Len(b$) And a$ <> b$ Then a$ = b$: Print a$ + " was pressed."

Loop

Just some food for thought for anyone who will need to monitor a key release like a same key tapping routine.

Pete

RE: Don't let INKEY$ byte you in the ASCII - PhilOfPerth - 02-01-2026

Nice one, @Pete. Compact and simple. I'll be adapting the clumsy "Response" in my programmes with this. Thanks.