[Code Snippet]How to shut down the computer on C#

[StructLayout(LayoutKind.Sequential, Pack=1)] 
internal struct TokPriv1Luid 
{ 
    public int Count; 
    public long Luid; 
    public int Attr; 
} 

[DllImport("kernel32.dll", ExactSpelling=true) ] 
internal static extern IntPtr GetCurrentProcess(); 

[DllImport("advapi32.dll", ExactSpelling=true, SetLastError=true) ] 
internal static extern bool OpenProcessToken( IntPtr h, int acc, ref IntPtr 
phtok ); 

[DllImport("advapi32.dll", SetLastError=true) ] 
internal static extern bool LookupPrivilegeValue( string host, string name, 
ref long pluid ); 

[DllImport("advapi32.dll", ExactSpelling=true, SetLastError=true) ] 
internal static extern bool AdjustTokenPrivileges( IntPtr htok, bool disall, 
   ref TokPriv1Luid newst, int len, IntPtr prev, IntPtr relen ); 

[DllImport("user32.dll", ExactSpelling=true, SetLastError=true) ] 
internal static extern bool ExitWindowsEx( int flg, int rea ); 

internal const int SE_PRIVILEGE_ENABLED = 0x00000002; 
internal const int TOKEN_QUERY = 0x00000008; 
internal const int TOKEN_ADJUST_PRIVILEGES = 0x00000020; 
internal const string SE_SHUTDOWN_NAME = "SeShutdownPrivilege"; 
internal const int EWX_LOGOFF = 0x00000000; 
internal const int EWX_SHUTDOWN = 0x00000001; 
internal const int EWX_REBOOT = 0x00000002; 
internal const int EWX_FORCE = 0x00000004; 
internal const int EWX_POWEROFF = 0x00000008; 
internal const int EWX_FORCEIFHUNG = 0x00000010; 


public static void DoExitWin( int flg ) 
{ 
   bool ok; 
   TokPriv1Luid tp; 
   IntPtr hproc = GetCurrentProcess(); 
   IntPtr htok = IntPtr.Zero; 
   ok = OpenProcessToken( hproc, TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, ref 
htok ); 
   tp.Count = 1; 
   tp.Luid = 0; 
   tp.Attr = SE_PRIVILEGE_ENABLED; 
   ok = LookupPrivilegeValue( null, SE_SHUTDOWN_NAME, ref tp.Luid ); 
   ok = AdjustTokenPrivileges( htok, false, ref tp, 0, IntPtr.Zero, 
IntPtr.Zero ); 
   ok = ExitWindowsEx( flg, 0 ); 
}