In order to lock your computer, you need to use the following two APIs:
[DllImport("user32.dll")] public static extern void LockWorkStation(); [DllImport("user32.dll")] public static extern int ExitWindowsEx(int uFlags, int dwReason);
You should implement it as follows:
// Lock computer void btnLock_Click(object sender, System.EventArgs e) { LockWorkStation(); }// Log Off void btnLogOff_Click(object sender, System.EventArgs e) { if(DialogResult.Yes==MessageBox.Show("Log Off?","Log Off", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2)) ExitWindowsEx(0, 0); } // Shutdown void btnShutdown_Click(object sender, System.EventArgs e) { if(DialogResult.Yes==MessageBox.Show("Shutdown?","Shutdown", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2)) ExitWindowsEx(1, 0 );