' 导入命名空间
Imports System.Windows
Imports System.Windows.Controls

Namespace VisualBasic
    ' Custom menu item that stores a reference to a window
    Public Class WindowMenuItem
        Inherits MenuItem
        Public Window As Window = Nothing
    End Class
End Namespace

' 导入命名空间
Imports System.Windows
Imports System.Windows.Controls

Namespace VisualBasic
    Partial Public Class MainWindow
        Inherits Window
        Public Sub New()
            InitializeComponent()
        End Sub

Private Sub MainWindow_Activated(ByVal sender As Object, ByVal e As EventArgs)
            Me.windowMenuItem.Items.Clear()
            Dim windowCount As Integer = 0
            For Each window As Window In Application.Current.Windows
                windowCount += 1
                Dim menuItem As New WindowMenuItem()
                menuItem.Window = window
                menuItem.Header = "_" & windowCount.ToString() & " Window " & windowCount.ToString()
                AddHandler menuItem.Click, AddressOf menuItem_Click
                Me.windowMenuItem.Items.Add(menuItem)
            Next window
        End Sub

        Private Sub menuItem_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
            Dim menuItem As WindowMenuItem = CType(sender, WindowMenuItem)
            menuItem.Window.Activate()
        End Sub
    End Class
End Namespace