private void comboBox_KeyDown(object sender, KeyEventArgs e)
if ((Keyboard.Modifiers & ModifierKeys.Control) > 0 && e.Key == Key.C)
If the combo box is active, and then you press ctrl+C, it's content will be copied to clipboard. I down't know if this is what you want. If you use data binding, you may want to use SelectedValue property, or convert SelectedItem to your type, and then get the text you want.