Control state is the essential state information needed even if view state is disabled. When an adapter needs to maintain its own control state information, it can override the ControlAdapter.LoadAdapterControlState(object) and ControlAdapter.SaveAdapterControlState methods.

An adapter might need to maintain control state information when there are features that need to have state maintained across requests, independent from the state of the associated control. For example, a composite control consisting of a large textual display and a group of System.Web.UI.WebControls.RadioButton controls might render as a single view on desktop computer browsers. On other browsers, it might split its rendering—one view for the textual display and the other for the radio button group. The adapter would need to maintain its own target-specific information about the currently active view.

The ControlAdapter.LoadAdapterControlState(object) method is called immediately after the System.Web.UI.Control.LoadControlState(object) method, in the LoadState lifecycle stage. The adapter control state is separate and in addition to the control state of the control.