blazor-devexpress-dot-blazor-dot-dxaccordion-237e9665.md
Fires when an item is about to be expanded and allows you to cancel the action.
Namespace : DevExpress.Blazor
Assembly : DevExpress.Blazor.v25.2.dll
NuGet Package : DevExpress.Blazor
[Parameter]
public Action<AccordionItemCancelEventArgs> BeforeExpand { get; set; }
The BeforeExpand event's data class is AccordionItemCancelEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Cancel | Specifies whether the action that raised the event should be canceled. |
| CausedByAPI | Obsolete. Specifies whether an event was triggered by user action or from code. Inherited from AccordionItemStateChangeEventArgs. |
| ItemInfo | Returns information about an item related to the event. Inherited from AccordionItemEventArgs. |
| Reason | Returns the reason why the Accordion item’s expanded state changed. Inherited from AccordionItemStateChangeEventArgs. |
The following code snippet cancels the expand action for root-level nodes:
<DxAccordion BeforeExpand="@BeforeExpand">
@* ... *@
</DxAccordion>
@code {
void BeforeExpand(AccordionItemCancelEventArgs e) {
if (args.ItemInfo.Level == 0) args.Cancel = true;
}
}
See Also