在不同的模式下实现定时关闭计算机

Option Explicit
Const SM_CLEANBOOT = 67
Const EWX_LOGOFF = 0
Const EWX_SHUTDOWN = 1
Const EWX_REBOOT = 2
Const EWX_FORCE = 4
Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags As Long, _
     ByVal dwReserved As Long) As Long
   
Private Declare Function GetSystemMetrics Lib "user32" (ByVal nIndex As Long) As Long
Private Declare Function GetTickCount Lib "kernel32" () As Long
Dim mytime As Date
Dim RUNTIME As Long
Private Sub Timer1_Timer()
   Dim HOUR As Integer
   Dim MIN As Integer
   Dim SEC As Integer
   Dim RUN As String
   Dim delay As Integer
   RUNTIME = GetTickCount() \ 1000
   HOUR = Int(RUNTIME \ 3600)
   MIN = (RUNTIME - 3600 * HOUR) \ 60
   SEC = RUNTIME - 3600 * HOUR - 60 * MIN
   RUN = HOUR & ":" & MIN & ":" & SEC
 
   Select Case GetSystemMetrics(SM_CLEANBOOT)
          Case 1: Label1.Caption = "安全模式已运行" & Format(RUN, "hH:Mm:Ss")
          Case 2: Label1.Caption = "网络安全模式已运行" & Format(RUN, "hH:Mm:Ss")
          Case Else: Label1.Caption = "正常模式已运行" & Format(RUN, "hH:Mm:Ss")
   End Select
   delay = (Val(Text1.Text) - RUNTIME \ 60 + mytime \ 60)
   If Text1.Enabled = False Then
      Label3.Caption = "距离关闭计算机还有 " & delay & " 分钟"
      If delay = 0 Then Call ExitWindowsEx(EWX_SHUTDOWN, 0)
   End If
End Sub
Private Sub Command1_Click()
   If Val(Text1.Text) * 60 > 60 Then
      Text1.Enabled = False
      mytime = RUNTIME
    Else
      MsgBox ("请输入关机时间，时间要大于1分钟！")
   End If
End Sub
Private Sub Command2_Click()
   Text1.Enabled = True
End Sub
Private Sub Command3_Click()
   End
End Sub