WM_MDIDESTROY  22HH_1P 

An application sends the WM_MDIDESTROY message to a multiple document interface (MDI) client window to close an MDI child window.

WM_MDIDESTROY

wParam = (WPARAM) (HWND) hwndChild; // handle of child to close

lParam = 0;                         // not used; must be zero

Parameters

hwndChild

Value of wParam. Identifies the MDI child window to be closed.

Return Values

This message always returns zero.

Remarks

This message removes the title of the MDI child window from the MDI frame window and deactivates the child window. An application should use this message to close all MDI child windows.

If an MDI client window receives a message that changes the activation of its child windows and the active MDI child window is maximized, Windows restores the active child window and maximizes the newly activated child window.

See Also