ControlTrackViewState Method

Causes tracking of view-state changes to the server control so they can be stored in the server control's StateBag object. This object is accessible through the property.

Namespace:   System.Web.UI
Assembly:  System.Web (in System.Web.dll)

protected virtual void TrackViewState()
virtual void TrackViewState()
abstract TrackViewState : unit -> unit
override TrackViewState : unit -> unit
Protected Overridable Sub TrackViewState

This method is called automatically at the end of the Init event in the server control's lifecycle.

Invoke this method when you develop templated data-bound controls. This method alerts ASP.NET to monitor changes to a server control's view state, which is required when you override the ControlDataBind method.


The following example overrides the DataBind method in a custom ASP.NET server control. It begins by calling the base OnDataBinding method and then uses the Clear method to delete all the child controls and the ClearChildViewState method to delete any saved view-state settings for those child controls. Finally, the property is set to true. The control then uses the property to determine whether view-state change tracking is enabled for the control. If it is not enabled, the TrackViewState method is called.

public override void DataBind() 
   // Reset the control's state.
   // Check for HasChildViewState to avoid unnecessary calls to ClearChildViewState.
   if (HasChildViewState)
   ChildControlsCreated = true;
   if (!IsTrackingViewState)
Public Overrides Sub DataBind()
   ' Reset the control's state.
   ' Check for HasChildViewState to avoid unnecessary calls to ClearChildViewState.
   If HasChildViewState Then
   End If
   ChildControlsCreated = True
   If Not IsTrackingViewState Then
   End If
End Sub
Version Information
.NET Framework
Available since 1.1
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