Control.LoadControlState(Object) Method

Reference

Definition

Namespace:: System.Web.UI

Assembly:: System.Web.dll

Important

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Restores control-state information from a previous page request that was saved by the SaveControlState() method.

protected public:
 virtual void LoadControlState(System::Object ^ savedState);

protected internal virtual void LoadControlState (object savedState);

abstract member LoadControlState : obj -> unit
override this.LoadControlState : obj -> unit

Protected Friend Overridable Sub LoadControlState (savedState As Object)

Parameters

savedState: Object

An Object that represents the control state to be restored.

Examples

The following code example overrides the LoadControlState method in a custom ASP.NET control. When this method is invoked, it determines whether control state was previously saved for the control and, if so, sets the internal property currentIndex to the saved value.

The OnInit method is overridden to call the RegisterRequiresControlState method on the Page to indicate that the custom control uses control state.

public class Sample : Control {
    private int currentIndex = 0;
   
    protected override void OnInit(EventArgs e) {
        Page.RegisterRequiresControlState(this);
        base.OnInit(e);
    }

    protected override object SaveControlState() {
        return currentIndex != 0 ? (object)currentIndex : null;
    }

    protected override void LoadControlState(object state) {
        if (state != null) {
            currentIndex = (int)state;
        }
    }
}

Class Sample
  Inherits Control
  
  Dim currentIndex As Integer
  
      Protected Overrides Sub OnInit(ByVal e As EventArgs)
          Page.RegisterRequiresControlState(Me)
          currentIndex = 0
          MyBase.OnInit(e)
      End Sub
  
      Protected Overrides Function SaveControlState() As Object
          If currentIndex <> 0 Then
              Return CType(currentIndex, Object)
          Else
              Return Nothing
          End If
      End Function
  
      Protected Overrides Sub LoadControlState(ByVal state As Object)
          If (state <> Nothing) Then
              currentIndex = CType(state, Integer)
          End If
      End Sub
  
End Class

Remarks

Override this method when you need to specify how a custom server control restores its control state. For more information, see ASP.NET State Management Overview.

Applies to

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