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EntityDataSource.ContextCreating Event

Definition

Occurs when the EntityDataSource creates the ObjectContext that is used to work with entity data objects.

public:
 event EventHandler<System::Web::UI::WebControls::EntityDataSourceContextCreatingEventArgs ^> ^ ContextCreating;
public event EventHandler<System.Web.UI.WebControls.EntityDataSourceContextCreatingEventArgs> ContextCreating;
member this.ContextCreating : EventHandler<System.Web.UI.WebControls.EntityDataSourceContextCreatingEventArgs> 
Public Custom Event ContextCreating As EventHandler(Of EntityDataSourceContextCreatingEventArgs) 

Event Type

Examples

The following example shows how to create an ObjectContext variable of the Page object and assign it to the Context property of the EntityDataSourceContextCreatingEventArgs object.

public partial class _Default : System.Web.UI.Page
    {
        AdventureWorksModel.AdventureWorksEntities objCtx =
            new AdventureWorksModel.AdventureWorksEntities();

        protected void EntityDataSource2_ContextCreating(object sender,
            EntityDataSourceContextCreatingEventArgs e)
        {
            e.Context = objCtx;
        }
    }

Remarks

Handle the ContextCreating event to supply your own ObjectContext instead of having a new ObjectContext created. If the ContextCreating event is not handled or the handler does not provide an ObjectContext, the EntityDataSource creates one according to its configuration. When an ObjectContext is provided to the ContextCreating event, the same instance is assigned to the Context property of the event object of successive events. For more information, see Object Context Life-Cycle Management (EntityDataSource). For more information about the object context, see Identity Resolution, State Management, and Change Tracking.

Applies to