TCN_SELCHANGING notification code
Notifies a tab control's parent window that the currently selected tab is about to change. This notification code is sent in the form of a WM_NOTIFY message.
Pointer to an NMHDR structure that contains additional information about this notification.
Returns TRUE to prevent the selection from changing, or FALSE to allow the selection to change.
To determine the currently selected tab, use the TabCtrl_GetCurSel macro.
Minimum supported client
|Windows Vista [desktop apps only]|
Minimum supported server
|Windows Server 2003 [desktop apps only]|