GlobalEventHandlers.onkeydown
The onkeydown
property of the
GlobalEventHandlers
mixin is an EventHandler
that
processes keydown
events.
The keydown
event fires when the user presses a keyboard key.
Syntax
target.onkeydown = functionRef;
Value
functionRef
is a function name or a function
expression. The function receives a KeyboardEvent
object as its
sole argument.
Example
This example logs the KeyboardEvent.code
value whenever you press down a
key inside the <input>
element.
HTML
<input>
<p id="log"></p>
JavaScript
const input = document.querySelector('input');
const log = document.getElementById('log');
input.onkeydown = logKey;
function logKey(e) {
log.textContent += ` ${e.code}`;
}
Result
Specifications
Specification | Status | Comment |
---|---|---|
HTML Living Standard The definition of 'onkeydown' in that specification. |
Living Standard |
Browser compatibility
BCD tables only load in the browser
Compatibility notes
Since Firefox 65, the keyup
and
keydown
events are now fired
during IME composition, to improve cross-browser compatibility for CJKT users
(bug 354358, also see keydown
and keyup events are now fired during IME composition for more useful details). To
ignore all keydown
events that are part of composition, do something like
this (229 is a special value set for a keyCode
relating to an event that
has been processed by an IME):
eventTarget.addEventListener("keydown", event => {
if (event.isComposing || event.keyCode === 229) {
return;
}
// do something
});
See also
keydown
event- Related event handlers