WindowListing is a feature that allows us to display the names of the various child forms in an MDI application in the drop down of a particular menu.
For Example: If there is a control known as MenuStrip1 and there are two parent menus known as File and Edit.
To display the list of child forms in the Edit Menu
Set the MdiWindowListItem property to ->Edit
If there are submenus below the Edit Menu, list of child forms will be displayed
after the last submenu.