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View this topic on docs.devexpress.com (Learn more)

GridControl.GroupRowExpanding Event

Occurs when a group row is about to be expanded, allowing cancellation of the action.

Namespace:DevExpress.UI.Xaml.Grid
Assembly:DevExpress.UI.Xaml.Grid.v18.1.dll

Expanded Syntax

Expanded Event Data

The event handler receives an argument of type DevExpress.UI.Xaml.Grid.RowAllowEventArgs containing data related to this event.

Expanded Remarks

The GroupRowExpanding event is raised before a group row is expanded by an end-user or in code, allowing you to cancel this action. The group row is identified by its handle via the RowHandle property. To prevent the group row from being expanded, set the event parameter's Allow parameter to false.

The ExpandAllGroups method allows you to expand all group rows. In this instance, the GroupRowExpanding event is raised only once. The event parameter's RowHandle property returns an invalid row handle (DataControlBase.InvalidRowHandle).

After the group row has been expanded, the GroupRowExpanded event is raised.

Expanded See Also

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