VBS 断网后自动关机30秒后

Dim Wsh,objWMIService,colMonitoredEvents
Set Wsh = WScript.CreateObject("WScript.Shell")
Set objWMIService = GetObject("winmgmts:\. ootwmi")
Set colMonitoredEvents = objWMIService.ExecNotificationQuery("Select * from MSNdis_StatusMediaDisconnect")
Do While True
Set strLatestEvent = colMonitoredEvents.NextEvent
Wsh.run "shutdown -s -t 30 -c "chr(34)"系统网络断开，机器即将关闭"chr(34)
Loop