An application sends the WM_MDINEXT message to a multiple-document interface (MDI) client window to activate the next or previous child window.
A handle to the MDI child window. The system activates the child window that is immediately before or after the specified child window, depending on the value of the lParam parameter. If the wParam parameter is NULL, the system activates the child window that is immediately before or after the currently active child window.
If this parameter is zero, the system activates the next MDI child window and places the child window identified by the wParam parameter behind all other child windows. If this parameter is nonzero, the system activates the previous child window, placing it in front of the child window identified by wParam.
The return value is always zero.
If an MDI client window receives any message that changes the activation of its child windows while the active MDI child window is maximized, the system restores the active child window and maximizes the newly activated child window.
Minimum supported client
|Windows 2000 Professional [desktop apps only]|
Minimum supported server
|Windows 2000 Server [desktop apps only]|