Returns all child and grandchild controls of of the specified type.

ControlsOfType.cs

/// <summary>
/// Returns all child and grandchild controls of of the specified type.
/// </summary>
/// <typeparam name="T">Type of control to look for</typeparam>
/// <param name="parent">Parent to get list of controls from</param>
/// <returns></returns>
public static IEnumerable<T> ControlsOfType<T>( this Control parent ) where T : Control
{
	foreach( Control child in parent.Controls )
	{
		if( child is T )
			yield return child as T;
		foreach( Control grandchild in child.ControlsOfType<T>() )
			yield return grandchild as T;
	}
}