BaseObjectSpace.SetPrefetchPropertyNames(Object, String[]) Method

Loads specified delayed properties and child collections in each object of a given list.

Namespace: DevExpress.ExpressApp

Assembly: DevExpress.ExpressApp.v23.2.dll

NuGet Package: DevExpress.ExpressApp

Declaration

C#

public virtual void SetPrefetchPropertyNames(
    object collection,
    params string[] propertyNames
)

VB.NET

Public Overridable Sub SetPrefetchPropertyNames(
    collection As Object,
    ParamArray propertyNames As String()
)

Parameters

Name	Type	Description
collection	Object	An IEnumerable list of parent objects.
propertyNames	String[]	Properties to load.

Remarks

Before a ListView is displayed, it may actively read properties of underlying data source items to calculate Conditional Appearance rules, actions’ TargetObjectsCriteria, or client-side filters. If filter conditions and appearance rules use Delayed Properties, call the SetPrefetchPropertyNames method before the ListView is opened to pre-load delayed properties and reduce a number of requiests to an underlying data source.

C#

using DevExpress.ExpressApp;
// ...
public class PreFetchOrdersViewController : ObjectViewController<ListView, Customer> {
    protected override void OnActivated() {
        if(View.CollectionSource.DataAccessMode == CollectionSourceDataAccessMode.Client) {
            ((BaseObjectSpace)ObjectSpace).SetPrefetchPropertyNames(View.CollectionSource.Collection, nameof(Customer.Orders));
        }
    }
}

VB.NET

Imports DevExpress.ExpressApp
' ...
Public Class PreFetchOrdersViewController
    Inherits ObjectViewController(Of ListView, Customer)
    Protected Overrides Sub OnActivated()
        If View.CollectionSource.DataAccessMode = CollectionSourceDataAccessMode.Client Then
            CType(ObjectSpace, BaseObjectSpace).SetPrefetchPropertyNames(View.CollectionSource.Collection, nameof(Customer.Orders))
        End If
    End Sub
End Class