Cancel the keydown in HTML

Question

How can I cancel the keydown of a specific key on the keyboard, for example(space, enter and arrows) in an HTML page.

Answer 1

If you're only interested in the example keys you mentioned, the keydown event will do, except for older, pre-Blink versions of Opera (up to and including version 12, at least) where you'll need to cancel the keypress event. It's much easier to reliably identify non-printable keys in the keydown event than the keypress event, so the following uses a variable to set in the keydown handler to tell the keypress handler whether or not to suppress the default behaviour.

var cancelKeypress = false;

document.onkeydown = function(evt) {
    evt = evt || window.event;
    cancelKeypress = /^(13|32|37|38|39|40)$/.test("" + evt.keyCode);
    if (cancelKeypress) {
        return false;
    }
};

/* For Opera */
document.onkeypress = function(evt) {
    if (cancelKeypress) {
        return false;
    }
};

Answer 2

Catch the keydown event and return false. It should be in the lines of:

<script>
document.onkeydown = function(e){
  var n = (window.Event) ? e.which : e.keyCode;
  if(n==38 || n==40) return false;
}
</script>

(seen here)

The keycodes are defined here

edit: update my answer to work in IE