How to change values of div when press key down

Question

I have made divs in my HTML that I use to draw bars with CSS. Now I want the to values change when the user presses the down arrow key.

This is my JavaScript:

var changeIdValue = function(id, value) {
document.getElementById(id).style.height = value;
};

window.addEventlistener("onkeydown", function(e){
if(e.keyCode == 40){
    changeIdValue("balklongwaarde", "60px");
});
}

I don't understand why this is not working.

Answer 1

You can say something like this

window.onkeydown = function(e){
        if(e.keyCode == 40)
            changeIdValue("balklongwaard", "60px");
        };