On key down example javascript
JavaScript
document.addEventListener("keypress", checkKeyPressed);
function checkKeyPressed(event) {
if (event.charCode == "97") {
console.log("The 'a' key is pressed.");
} else if (event.charCode == "122") {
console.log("it is a z expression");
} else {
console.log("key down: " + String.fromCharCode(event.keyCode));
}
}