Adding elements to a Form in JavaScript

I came across this code (sorry dont remember the web site) that I have posted in
response to many of the posts related to this type of problem. I thought it would
be easier if I post this code here for others to find.
/// <_summary>
/// Finds a Control recursively. Note finds the first match that exists
///
/// <_param name="ContainerCtl">Should be the lowest container in the heirarchy,
for eg dont choose Master page if you can pick the specific panel
/// <_param name="IdToFind">ID of the control you are looking for
/// <_returns>the control if found else null
_private static Control _FindControlRecursive(Control Root, string Id)
{
if (Root.ID == Id)
return Root;
foreach (Control Ctl in Root.Controls)
{
Control FoundCtl = FindControlRecursive(Ctl, Id);
if (FoundCtl != null)
return FoundCtl;
}
return null;
}