TreeView.OnBeforeCollapse(TreeViewCancelEventArgs) Method
Definition
Raises the BeforeCollapse event.
protected public:
virtual void OnBeforeCollapse(System::Windows::Forms::TreeViewCancelEventArgs ^ e);
protected:
virtual void OnBeforeCollapse(System::Windows::Forms::TreeViewCancelEventArgs ^ e);
protected internal virtual void OnBeforeCollapse (System.Windows.Forms.TreeViewCancelEventArgs e);
protected virtual void OnBeforeCollapse (System.Windows.Forms.TreeViewCancelEventArgs e);
abstract member OnBeforeCollapse : System.Windows.Forms.TreeViewCancelEventArgs -> unit
override this.OnBeforeCollapse : System.Windows.Forms.TreeViewCancelEventArgs -> unit
Protected Friend Overridable Sub OnBeforeCollapse (e As TreeViewCancelEventArgs)
Protected Overridable Sub OnBeforeCollapse (e As TreeViewCancelEventArgs)
Parameters
A TreeViewCancelEventArgs that contains the event data.
Remarks
Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.
The OnBeforeCollapse 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 OnBeforeCollapse(TreeViewCancelEventArgs) in a derived class, be sure to call the base class's OnBeforeCollapse(TreeViewCancelEventArgs) method so that registered delegates receive the event.