Need some javascript help

[mindspun]

<script>
function clickPost(el){
	var im=el.parentNode.style.backgroundImage;
	var sp0=im.split("/");
	var sp1=sp0[sp0.length-1].split(".");
	document.getElementById("formInp").value=sp1[0];
	document.F.submit();
}
</script>

<div class="thumb" style="background-image: url('images/1.jpg');"><a href='javascript:void(0)' onclick='clickPost(this)'>

This code above snags the number from the background-image file, I changed my code around and I believe I need to go to a childnode now to grab the number from the img src but am having issues figuring it out. Thanks

Below is the current code for displaying the thumbs:

<div id="container">
<a href='javascript:void(0)' onclick='clickPost(this)'><div class="overlay"></div>
<div class="image"><img src="images/2.jpg" /></a></div>
</div>

[devnull69]

This is illegal HTML

<div id="container">
  <a href='javascript:void(0)' onclick='clickPost(this)'>
    <div class="overlay"></div>
    <div class="image">
      <img src="images/2.jpg" />
  </a>
    </div>
</div>

An anchor is an inline element and must not contain block level elements. On top of that your element nesting is flawed.