private void addMenus(MenuStrip ms) { SuspendLayout(); ToolStripMenuItemEx fileOpenMenuItem = new(fileOpenEventHandler) { Text = @"&Open", ShortcutKeys = Keys.Control | Keys.O, }; ToolStripMenuItemEx exitMenuItem = new((_, _) => Application.Exit()) { Text = @"E&xit", ShortcutKeys = Keys.Alt | Keys.F4, }; ToolStripMenuItemEx fileMenu = new() { Text = @"&File", DropDownItems = { fileOpenMenuItem, new ToolStripSeparator(), exitMenuItem } }; ToolStripMenuItemEx closeAllWindowsMenuItem = new( (_, _) => MdiChildren.forEach((f) => f.Close()) ) { Text = @"&Close all", ShortcutKeys = Keys.Control | Keys.X, }; ToolStripMenuItemEx windowMenu = new() { Text = @"&Windows", DropDownItems = { closeAllWindowsMenuItem, } }; ms.MdiWindowListItem = windowMenu; ms.Items.add(fileMenu, /*actionMenu,*/ windowMenu); ResumeLayout(); }