Get All Web Controls of a Specific Type on a Page

Question

I have been pondering how I can get all controls on a page and then perform a task on them in this related question:

How to Search Through a C# DropDownList Programm

Answer 1

        var dropDownLists = new List();
        foreach (var control in this.Controls)
        {
            if (control is DropDownList)
            {
                dropDownLists.Add( (DropDownList)control );
            }
        }