Hi Handoko,
Thank you for your answer.
I got a result after the test.
When the ComboBox is pulled down, the keys ESC, TAB, Enter have the same key value (Key = 0).
When the ComboBox is closed, I got
ESC Key= 27
TAB Key= 9
Enter Key= 13
These are the correct key values.
But I hope I can get it when the ComboBox is pulled down. Just like the Key F4.
Thanks.
PS. I like "Key.ToString" ^_^