Handling a 'keydown' event is rather simple.
You simply listen for the event, then check for the key you are interested in.
For example, this code listens for the keys "b" and "n":
const pre = document.querySelector('pre');
pre.innerText = "";
window.addEventListener('keydown', event => {
// console.log('keydown event:', event);
pre.innerText += `keydown event.key: "${event.key}"
`;
if (event.key === 'b') {
alert('You pressed "b"');
} else if (event.key === 'n') {
alert('You pressed "n"');
}
});
document.querySelector('button').onclick = () => {pre.innerText = ""};
<h4>Logging 'keydown' Events</h4>
<button>Clear Log</button>
<pre></pre>
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