Visual Basic Programming Code Examples

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Shutdown restart logoff the local machine

Shutdown restart logoff the local machine

The following API Declares and Constants can be used to force a PC to restart. Note, a demonstration routine can be found at the end of this post.

Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags as Long, ByVal wReserved as Long) as Long


Private Const EWX_FORCE = 4     'Force any applications to quit instead of prompting the user to close them.
Private Const EWX_POWEROFF = 8  'Shut down the system and, if possible, turn the computer off.
Private Const EWX_LOGOFF = 0    'Log off the network
Private Const EWX_REBOOT = 2    'Perform a full reboot of the system
Private Const EWX_SHUTDOWN = 1  'Shut down the system

'Purpose     :  Forces a machine shut down/logoff
'Inputs      :  [lShutDownType]                 If unspecified, will reboot the machine else one of the above constants
'Outputs     :  If successful returns a number other than zero
'Notes       :  If this fails check the value of Err.LastDllError. If this is 1314 then
'               the you do not have sufficient privileges to call this function.


Function MachineShutDown(Optional lShutDownType As Long = EWX_REBOOT) As Long
    MachineShutDown = ExitWindowsEx(lShutDownType, 0&) 'shut down the computer
End Function

'Purpose     :  Forces a machine shut down/logoff
'Inputs      :  N/A
'Outputs     :  N/A
'Notes       :  DOESN'T REQUIRE ANY PRIVILAGES


Sub MachineShutDown2()
    Shell "rundll32.exe user32.dll, ExitWindowsEx", vbHide
End Sub

'Demonstration routine
Sub Test()
    'Forces the computer to reboot
    'When the EWX_FORCE flag is set, Windows does not send the messages WM_QUERYENDSESSION and 
    'WM_ENDSESSION to the applications currently running in the system. This can cause the 
    'applications to lose data. Therefore, you should only use this flag in an emergency.
    Call MachineShutDown(EWX_FORCE Or EWX_REBOOT)
    'Forces the user to log off
    Call MachineShutDown(EWX_LOGOFF)
    'Shuts the computer down (no restart)
    Call MachineShutDown(EWX_SHUTDOWN)
    'Shuts the computer down and turns power off (if possible)
    Call MachineShutDown(EWX_POWEROFF)
End Sub