FindControlByID

When we want to find a control by its ID, chances are it is usually nested in many levels. In this scenario, we need more powerful method than the .NET framework provided Control.FindControl.

Writing such a method actually is straightforward enough:

private static Control FindControlByID(Control root, string id)
{
if (id == string.Empty)
return null;

if (root.ID == id)
return root;

foreach (Control c in root.Controls)
{
Control t = FindControlByID(c, id);
if (t != null)
{
return t;
}
}
return null;
}

It works great no matter there is master page involved or not; no matter how many levels the control hierarchy has.