Call Dispose when you are finished using the Control. The Dispose method leaves the Control in an unusable state. After calling this method, you must release all references to the control so the memory it was occupying can be reclaimed by garbage collection.
The following code example overrides the Dispose method to close the HtmlTextWriter object associated with a control, and call the Dispose method on a Button control, named myButton. If an Exception is thrown when this version of the Dispose method is called, the control writes a message to the current HttpResponse object.