CollectionSourceBase.CollectionChanging Event

Occurs before the Collection Source’s collection has been recreated.

Namespace: DevExpress.ExpressApp

Assembly: DevExpress.ExpressApp.v25.2.dll

NuGet Package: DevExpress.ExpressApp

Declaration

C#

public event EventHandler CollectionChanging

VB.NET

Public Event CollectionChanging As EventHandler

Event Data

The CollectionChanging event's data class is EventArgs.

Remarks

This event is raised in the CollectionSourceBase.ResetCollection method, before recreation of the Collection Source’s collection takes place. Handle the CollectionChanging event to be notified when the Collection Source’s collection is about to be recreated.

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the CollectionChanging event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

xaf-how-to-show-the-number-of-nested-list-views-items-in-tab-captions/CS/EFCore/TabCountEF/TabCountEF.Win/Controllers/ContactDetailViewWinController.cs#L42

UpdateLayoutGroupText();
View.CollectionSource.CollectionChanging += CollectionSource_CollectionChanging;
View.CollectionSource.CollectionChanged += CollectionSource_CollectionChanged;