TreeViewControl.NodeExpanding Event

Occurs before a node is expanded.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v20.2.dll

NuGet Packages: DevExpress.WindowsDesktop.Wpf.Grid.Core, DevExpress.Wpf.Grid.Core

Declaration

C#

public event TreeViewNodeAllowEventHandler NodeExpanding

VB.NET

Public Event NodeExpanding As TreeViewNodeAllowEventHandler

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.