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4/8/2010

This message sets the number of bytes per tab reserved for application-defined data in a tab control. You can send this message explicitly or by using the TabCtrl_SetItemExtramacro.

Syntax 

TCM_SETITEMEXTRA 
wParam = (WPARAM)(int) 
cb; 

lParam = 0;

Parameters

cb

Number of extra bytes.

lParam

Not used.

Return Value

TRUE indicates success. FALSE indicates failure.

Remarks

By default, the number of extra bytes is four. An application that changes the number of extra bytes cannot use the TCITEMstructure to retrieve and set the application-defined data for a tab. Instead, you must define a new structure that consists of the TCITEMHEADERstructure followed by application-defined members.

Requirements

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

See Also