How to make everything in a textfield be capital letters / uppercase?

Question

I want to make everything I write in a textfield to be capital letters. As I write, not after losing focus.

How do I do this using jQuery?

Answer 1

Use
oninput='this.value=this.value.toUpperCase();
This event is just for such cases, is fired after user input (pressing key) but before updating (displaying value), so with this typed text won't flicker while converting, and value is also correct (not like using only style to alter display without changing real data).