WASD Demo

HTML

<h1 style="color: red;">CLICK IN THIS BOX FIRST</h1>

JavaScript

var KEY = {
    WASD_LEFT:  65,
    WASD_RIGHT: 68,
    WASD_UP:    87,
    WASD_DOWN:  83
}

document.onkeydown = function (e) {
    console.log(e.keyCode)
    switch (e.keyCode) {
        case KEY.WASD_LEFT:
            alert('Left');
            break;
        case KEY.WASD_RIGHT:
            alert('Right');
            break;
        case KEY.WASD_UP:
            alert('Up');
            break;
        case KEY.WASD_DOWN:
            alert('Down');
            break;

        default:
            return; // exit this handler for other keys
    }
};