C#: In a KeyDown event, what should I use to check what key is down?

Question

In a KeyDown event, I have the KeyEventArgs to work with. It has (among other things) these three properties:

• e.KeyCode
• e.KeyData
• e.KeyValue

Which one should I use for what?

Answer 1

Edit: Somehow I misread your question to include checking a valid character. Did you modify it? I've added a description of each.

• KeyCode is the Keys enumeration value for the key that is down
• KeyData is the same as KeyCode, but combined with any SHIFT/CTRL/ALT keys
• KeyValue is simply an integer representation of KeyCode

If you just need the character, I'd probably recommend using the KeyPress event and using the KeyPressEventArgs.KeyChar property. You can then use Char.IsLetterOrDigit() to find out if it's a valid character.

Alternatively, you might be able to cast KeyEventArgs.KeyCode to a char and then use Char.IsLetterOrDigit on that.