Re: Safely reading text from HWND

From:
"Giovanni Dicanio" <giovanni.dicanio@invalid.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Tue, 20 May 2008 09:57:07 +0200
Message-ID:
<OGCxS9kuIHA.3780@TK2MSFTNGP03.phx.gbl>
"David Ching" <dc@remove-this.dcsoft.com> ha scritto nel messaggio
news:uZsYj.4590$7k7.2736@flpi150.ffdc.sbc.com...

// To avoid MFC:

// Get text length
int numChars = GetWindowTextLength(hwndUnknown);

// Note: If the HWND is in a different thread, the text could have
changed
// after we called GetWindowTextLength() and before this call to
GetWindowText()
// Not sure how MFC works around this issue; I suspect it doesn't.

// Get Text
TCHAR buf[nNumChars+1]; // +1 for NULL
GetWindowText (hwndUnknown, buf, _countof(buf));


Hi David,

Just a little note: I think that you can't define an array like you did,
because nNumChars is a run-time value, so the compiler can't reserve space
for that array at static (compile time).
(Of course your general idea is nice!)

I would use std::vector for the dynamic array, e.g.

 std::vector< TCHAR > buf( nNumChars + 1);

 GetWindowText( hwndUnknown, &buf[0], buf.size() );

Please correct me if I'm wrong.

Thanks,
G

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