JSFiddle - React, Tailwind, and code Playground

by lollero

HTML

Click in this frame, then try holding down some keys :)

<div id="out"></div>

JavaScript

var map = {18: false, 38: false, 40: false};
$(document).keydown(function(e) {
    if (e.which in map) {
        map[e.which] = true;
        
        if (map[18] && map[38]) {
            console.log( 'Alt + Up' );
        }
        else if (map[18] && map[40]) {
            console.log( 'Alt + Down' );
        }
        
    }
}).keyup(function(e) {
    if (e.which in map) {
        map[e.which] = false;
    }
});