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LB_GETTEXTLEN

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Windows Embedded CE 6.0 R3

4/8/2010

This message is sent by an application to retrieve the length of a string in a list box.

Syntax

LB_GETTEXTLEN wParam = (WPARAM) index; 
    lParam = 0;

Parameters

  • index
    Zero-based index of the string.
  • lParam
    Not used.

Return Value

The length of the string, in characters and excluding the terminating null character, indicates success. Under certain conditions, this value may actually be greater than the length of the text. For more information, see the following Remarks section.

LB_ERR indicates that the index parameter does not specify a valid index.

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.

Requirements

Header winuser.h
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also

Reference

GetWindowText
CB_GETLBTEXT
LB_GETTEXT
WM_GETTEXT
List Boxes Messages