TreeView.Expanding Event
Definition
Important
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Occurs when a node in the tree starts to expand.
Equivalent WinUI 2 API for UWP: Microsoft.UI.Xaml.Controls.TreeView.Expanding (for WinUI in the Windows App SDK, see the Windows App SDK namespaces).
// Register
event_token Expanding(TypedEventHandler<TreeView, TreeViewExpandingEventArgs const&> const& handler) const;
// Revoke with event_token
void Expanding(event_token const* cookie) const;
// Revoke with event_revoker
TreeView::Expanding_revoker Expanding(auto_revoke_t, TypedEventHandler<TreeView, TreeViewExpandingEventArgs const&> const& handler) const;public event TypedEventHandler<TreeView,TreeViewExpandingEventArgs> Expanding;function onExpanding(eventArgs) { /* Your code */ }
treeView.addEventListener("expanding", onExpanding);
treeView.removeEventListener("expanding", onExpanding);
- or -
treeView.onexpanding = onExpanding;Public Custom Event Expanding As TypedEventHandler(Of TreeView, TreeViewExpandingEventArgs)