Javascript variable null error?
<p>Hi there I found an error in my javascript code using firebug, '<strong>b is null</strong>' and my images are not changing.What I am trying to implement is 3 images swapping eventually on a webpage but standalone at the moment.Currently nothing is happening with it and I have tested in 3 well known browsers.</p>

<p>Any help would be great  </p>

<pre><code>&lt;script type="text/javascript"&gt;  
var ImageArr1 = new Array("banner1.jpg","banner2.jpg","banner3.jpg");
var ImageHolder1 = document.getElementById("photo");

function RotateImages(whichHolder,Start)
{
    var a = eval("ImageArr"+whichHolder);
    var b = eval("ImageHolder"+whichHolder);
    if(Start&gt;=b.length)
        Start=0;
    b.src = a[Start];
    document.getElementById('slideNumber').textContent = "Slide "+(Start+1)+" of         "+ImageArr1.length;
    window.setTimeout("RotateImages("+whichHolder+","+(Start+1)+")",3500);
}

RotateImages(1,0);
&lt;/script&gt;
</code></pre>
