>In the keypress of the textbox or combobox the CTRL + V or paste it cannot detect. How can I detect that action?
If you want to do cut, copy & paste, the best option, I think, is to enable the mouse menu. Create a "quick menu" look at the commands generated, and copy them to your own menu.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)