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OnTreeNodeExpanded Method

TreeView.OnTreeNodeExpanded Method

Raises the TreeNodeExpanded event of the TreeView control.

Namespace:  System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)

protected virtual void OnTreeNodeExpanded(
	TreeNodeEventArgs e
)

Parameters

e
Type: System.Web.UI.WebControls.TreeNodeEventArgs

A TreeNodeEventArgs that contains event data.

The TreeNodeExpanded event is raised when a node is expanded in the TreeView control. This allows you to provide an event-handling method that performs a custom routine whenever this event occurs.

NoteNote

If the SelectAction property for a node is set to Expand or SelectExpand, the TreeNodeExpanded event is also raised when that node is clicked in the TreeView control.

Raising an event invokes the event handler through a delegate. For more information, see Consuming Events.

The OnTreeNodeExpanded method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding the OnTreeNodeExpanded method in a derived class, be sure to call the OnTreeNodeExpanded method for the base class so that registered delegates receive the event.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0
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