PageStatePersister.ControlState Property

Definition

Namespace:

System.Web.UI

Assembly:

System.Web.dll

Gets or sets an object that represents the data that controls contained by the current Page object use to persist across HTTP requests to the Web server.

public:
 property System::Object ^ ControlState { System::Object ^ get(); void set(System::Object ^ value); };

public object ControlState { get; set; }

member this.ControlState : obj with get, set

Public Property ControlState As Object

Property Value

Object

An object that contains view state data.

Examples

The following code example demonstrates how a class that derives from the PageStatePersister class initializes the ControlState property. In this example, the ControlState property has been assigned to the Second field of a Pair object, and serialized using the ObjectStateFormatter class. When the Load method is called, the ObjectStateFormatter class is used to deserialize view state and control state information, and the ControlState property is initialized from the resulting Pair object's Second field. This code example is part of a larger example provided for the PageStatePersister class.

//
// Load ViewState and ControlState.
//
public override void Load()
{
    Stream stateStream = GetSecureStream();

    // Read the state string, using the StateFormatter.
    StreamReader reader = new StreamReader(stateStream);

    IStateFormatter formatter = this.StateFormatter;
    string fileContents = reader.ReadToEnd();

    // Deserilize returns the Pair object that is serialized in
    // the Save method.
    Pair statePair = (Pair)formatter.Deserialize(fileContents);

    ViewState = statePair.First;
    ControlState = statePair.Second;
    reader.Close();
    stateStream.Close();
}

'
' Load ViewState and ControlState.
'
Public Overrides Sub Load()

    Dim stateStream As Stream
    stateStream = GetSecureStream()

    ' Read the state string, using the StateFormatter.
    Dim reader As New StreamReader(stateStream)

    Dim serializedStatePair As String
    serializedStatePair = reader.ReadToEnd
    Dim statePair As Pair

    Dim formatter As IStateFormatter
    formatter = Me.StateFormatter

    ' Deserilize returns the Pair object that is serialized in
    ' the Save method.      
    statePair = CType(formatter.Deserialize(serializedStatePair), Pair)

    ViewState = statePair.First
    ControlState = statePair.Second
    reader.Close()
    stateStream.Close()
End Sub

Remarks

Control state is an object comprised of critical view state data that Web server controls need to function, and is contained in a separate object from normal view state information. Control state data is not affected when view state is disabled at the Page level, but requires extra implementation steps to use. For more information on using the ViewState property and control state when developing controls, see Developing Custom ASP.NET Server Controls.