How do I use the Enter key as an event handler (javascript)? [duplicate]

Question

im trying to make my own chat... so i have an input text field, the submit button, isn't even submit, its just a button.... so when the enter key is pressed, i need the value of the input field to appear in my textarea (which is readonly)...

well look.. make long story short, i just want a basic enter key event handler, i know it works perfectly with submit buttons cus you don't need to program anything at all, its default. but my button is type="button" .... so when you press enter nothing happens... how do i trigger my button by pressing enter?

Answer 1

Here is a version of the currently accepted answer (from @entonio) with key instead of keyCode:

HTML:

<input onkeyup="inputKeyUp(event)" ...>

Plain javascript:

function inputKeyUp(e) {
    if (e.key === 'Enter') {
        // submit
    }
}