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V24.2

DevExpress v24.2 Update — Your Feedback Matters

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TreeViewControl.NodeExpanding Event

Occurs before a node is expanded.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v24.2.dll

NuGet Package: DevExpress.Wpf.Grid.Core

#Declaration

public event TreeViewNodeAllowEventHandler NodeExpanding

#Event Data

The NodeExpanding event's data class is DevExpress.Xpf.Grid.TreeList.TreeViewNodeAllowEventArgs.

#Remarks

This event occurs when a user tries to expand a node. You can handle this event to cancel the action. To do this, set the event parameter’s TreeListNodeAllowEventArgs.Allow property to false.

After a user expands a node, the TreeViewControl raises the NodeExpanded event.

See Also