TreeView.OnTreeNodeExpanded(TreeNodeEventArgs) Method
Definition
Important
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Raises the TreeNodeExpanded event of the TreeView control.
protected:
virtual void OnTreeNodeExpanded(System::Web::UI::WebControls::TreeNodeEventArgs ^ e);protected virtual void OnTreeNodeExpanded (System.Web.UI.WebControls.TreeNodeEventArgs e);abstract member OnTreeNodeExpanded : System.Web.UI.WebControls.TreeNodeEventArgs -> unit
override this.OnTreeNodeExpanded : System.Web.UI.WebControls.TreeNodeEventArgs -> unitProtected Overridable Sub OnTreeNodeExpanded (e As TreeNodeEventArgs)Parameters
A TreeNodeEventArgs that contains event data.
Remarks
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.
Note
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 about how to handle events, see Handling and Raising 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(TreeNodeEventArgs) method in a derived class, be sure to call the OnTreeNodeExpanded(TreeNodeEventArgs) method for the base class so that registered delegates receive the event.
