The PageStatePersister property uses the GetStatePersister method to return the object, derived from the PageStatePersister class, that forms and extracts the combined control and view states for the page. If there is no derived page adapter attached to the page, a HiddenFieldPageStatePersister object is used to maintain the state in a hidden field on the page.
Notes to Implementers:
View state data stored by the PageStatePersister object in the internal ClientState property of the System.Web.UI..::.Page will always be saved in the hidden field on the Web page.
Notes to Inheritors:
When you inherit from the PageAdapter class, you can override the GetStatePersister method to return another derived page state persister if it is not feasible to maintain the combined state in a hidden field (for example, because of limited resources).
The GetStatePersister base class returns a HiddenFieldPageStatePersister object. You can use the SessionPageStatePersister class to maintain the page state in session state.