问内存泄漏Directory.GetFiles() VB.NET

EN

Private Sub tmr_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles tmr.Tick
    IndexStartMenu()
    GC.Collect()
End Sub

Private Sub IndexStartMenu()

    Dim startMenu As IO.DirectoryInfo
    Dim shortcuts() As IO.FileInfo

    'Enumerate current user's start menu
    startMenu = New IO.DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.StartMenu))
    shortcuts = startMenu.GetFiles("*.lnk", IO.SearchOption.AllDirectories)
    For Each lnk As IO.FileInfo In shortcuts
        Dim newRow As DataRow = dtApps.NewRow
        newRow("Application") = IO.Path.GetFileNameWithoutExtension(lnk.FullName)
        newRow("Window") = "Launch"
        newRow("Hwnd") = ""
        newRow("IsShortcut") = True
        newRow("ShortcutPath") = lnk.FullName
        dtApps.LoadDataRow(newRow.ItemArray, LoadOption.Upsert)
        newRow = Nothing
    Next

    'Enumerate all users' start menu
    startMenu = New IO.DirectoryInfo(allUsersStartMenuPath)
    shortcuts = startMenu.GetFiles("*.lnk", IO.SearchOption.AllDirectories)
    For Each lnk As IO.FileInfo In shortcuts
        Dim newRow As DataRow = dtApps.NewRow
        newRow("Application") = IO.Path.GetFileNameWithoutExtension(lnk.FullName)
        newRow("Window") = "Launch"
        newRow("Hwnd") = ""
        newRow("IsShortcut") = True
        newRow("ShortcutPath") = lnk.FullName
        dtApps.LoadDataRow(newRow.ItemArray, LoadOption.Upsert)
        newRow = Nothing
    Next

    'Trying to fix memory usage
    startMenu = Nothing
    Array.Clear(shortcuts, 0, shortcuts.Length)
    shortcuts = Nothing
End Sub