PC 1시간뒤 자동 종료되게 하기

Public Class frmShutDown

    Private Target As DateTime

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Button1.Enabled = False
        Target = DateTime.Now.AddHours(1)
        Timer1.Interval = 1000
        Timer1.Start()
    End Sub

    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
        Dim TS As TimeSpan = Target.Subtract(DateTime.Now)
        Label1.Text = TS.ToString("hh\:mm\:ss")
        If TS.TotalMilliseconds <= 0 Then
            Timer1.Stop()
            Shell("shutdown -s")
        End If
    End Sub

End Class