Instead of using the standard WebForms-supplied components in your application’s user interface, you can use your own custom-designed components. For example, you could substitute an oval-shaped push button for the standard Forms rectangular shape.
The user interface elements (i.e., control item types) that can be replaced are:
The standard user interface components implement WebForm’s IView
interface. By creating your own class for your custom user interface component
that implements this interface, your custom component can substitute for the
standard component and be integrated into your Forms application.