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Overview |
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Group |
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Quick Info
Windows NT
| Yes
| Win95
| Yes
| Win32s
| Yes
| Import Library
| -
| Header File
| winuser.h
| Unicode
| No
| Platform Notes
| Windows 95: wParam is 16-bits
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LB_GETTEXTLEN
An application sends an LB_GETTEXTLEN message to retrieve the length of a
string in a list box.
LB_GETTEXTLEN
wParam = (WPARAM) index; // item index
lParam = 0; // not used; must be zero
Parameters
index
Value of wParam. Specifies the zero-based index of the string.
Windows 95: The wParam parameter is limited to 16-bit values. This means list boxes cannot contain
more than 32,767 items. Although the number of items is restricted, the total
size in bytes of the items in a listbox is limited only by available memory.
Return Values
The return value is the length of the string, in characters, excluding the
terminating null character. Under certain conditions, this value may actually be
greater than the length of the text. For more information, see the following
Remarks section.
If the index parameter does not specify a valid index, the return value is LB_ERR.
Remarks
Under certain conditions, the return value is larger than the actual length of
the text. This occurs with certain mixtures of ANSI and Unicode, and is due to
the operating system allowing for the possible existence of double-byte
character set (DBCS) characters within the text. The return value, however, will
always be at least as large as the actual length of the text; you can thus always
use it to guide buffer allocation. This behavior can occur when an application
uses both ANSI functions and common dialogs, which use Unicode.
To obtain the exact length of the text, use the WM_GETTEXT, LB_GETTEXT, or
CB_GETLBTEXT messages, or the GetWindowText function.
See Also
CB_GETLBTEXT, GetWindowText, LB_GETTEXT, WM_GETTEXT
Related Links
Software for Delphi and C++ Builder developers
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More Online Helps
Win32 Multimedia Programmer's Reference (mmedia.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (tapi.hlp)
Unix Manual Pages
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