Update URL with JavaScript doesn't work

Question

I'm trying to change the url of some tag using another one. Can't get it to work. Please help.

Here's my code:

<a href="#" rel="wd" onclick="updateUrl('wd')">Category</a>

<a id="test" href="index.php?path=portfolio/web" class="thumbnail"><img src="img.jpg"></a>

<script type="text/javascript">
function updateUrl(newUrl)
{
    document.links["test"].href .= newUrl;
}
</script>

Answer 1

document.links['test'].href += newUrl;