How to create button for traffic light code in javascript?

Question

I intend to include a button in my traffic light code so that the user can click on it to activate the traffic light however, i am unsure of where to place it in my code.

Answer 1

Place the button wherever you like inside the body tag.

<input type="button" name="start" value="Start/stop Traffic light" onclick="startStop()">

Remove the setTimeout and the slideit() initial call.

var step=1;
function slideit()
{
    document.images.slide.src = eval("image"+step+".src");
    if(step<4)
        step++;
    else
        step=1;
}

And add the startStop function below and the working variable declaration.

var working;
function startStop() {
    if (typeof working != 'undefined') working = clearInterval(working);
    else working=setInterval("slideit()", 3000);
}