#锁定#
[DllImport("user32.dll")]
private static extern void LockWorkStation();
#重启#
public static void res()
{
    Process process = new Process();
    process.StartInfo.FileName = "cmd.exe";
    process.StartInfo.RedirectStandardInput = true;
    process.StartInfo.RedirectStandardOutput = true;
    process.StartInfo.RedirectStandardError = true;
    process.StartInfo.UseShellExecute = false;
    process.StartInfo.CreateNoWindow = true;
    process.Start();
    process.StandardInput.WriteLine("shutdown -r -t 0");
}
#关机#
public static void close()
{
    Process process = new Process();
    process.StartInfo.FileName = "cmd.exe";
    process.StartInfo.RedirectStandardInput = true;
    process.StartInfo.RedirectStandardOutput = true;
    process.StartInfo.RedirectStandardError = true;
    process.StartInfo.UseShellExecute = false;
    process.StartInfo.CreateNoWindow = true;
    process.Start();
    process.StandardInput.WriteLine("shutdown -s -t 0");
}
#注销#
[DllImport("user32.dll", CharSet = CharSet.Ansi)]
public static extern int ExitWindowsEx(int a, int b);
调用:Form1.ExitWindowsEx(0, 0);