Content Freeze
As of July 25th, 2023, there is a content freeze on this page.
This function cancels an event and prevents it from bubbling up.
Parameters:
- event – reference to the event to cancel
Example:
The following can be used on the onkeydown event to restrict which keys can be pressed.
function gradeKeys(event, element) {
var key = event.keyCode;
switch (key) {
case 65: // allow A
case 66: // allow B
case 67: // allow C
case 68: // allow D
case 70: // allow F
case 8: // allow backspace
case 46: // allow delete
case 37: // allow left arrow
case 39: // allow right arrow
case 40: // allow down arrow
case 38: // allow up arrow
case 13: // allow enter
break;
default: // disallow all other keys
preventEvent(event);
}
}