private void CaffeineMenuEventHandler(object sender, EventArgs e) { System.Windows.Forms.MenuItem menuitem = sender as System.Windows.Forms.MenuItem; if (menuitem != null) { if (menuitem.Checked) { // reverse-of-being-checked action Caffeine.unlockSleepMode(); } else { Caffeine.lockSleepMode(); } menuitem.Checked = !menuitem.Checked; } }