Enable or disable DIV tag and its inner controls using Javascript

Today, I was searching for a solution to enable/disable DIV element using javascript. I have tried so many code, but all are working in IE only and not supported by FF (firefox). At last I found some solution which is helpful. I thought this might also useful to you.

Copy/Paste following javascript code snippet.
<script type="text/javascript">
function toggleAlert() {
toggleDisabled(document.getElementById("content"));
}
function toggleDisabled(el) {
try {
el.disabled = el.disabled ? false : true;
}
catch(E){
}
if (el.childNodes && el.childNodes.length > 0) {
for (var x = 0; x < el.childNodes.length; x++) {
toggleDisabled(el.childNodes[x]);
}
}
}
</script>


Copy/Paste following HTML code in BODY tag:

<div id="content">
<table>
<tr>
<td><input type="text" name="foo" /></td>
</tr>
<tr>
<td>
<select name="bar">
<option>a</option>
<option>b</option>
<option>c</option>
</select>
</td>
</tr>
</table>
</div>
<input type="checkbox" value="toggleAlert()" onclick="toggleAlert()" />

Here, I have used one checkbox, by clicking which you can enable/disable child controls of a DIV. However, you can use any element other than checkbox (e.g button, radio button, etc…)