OnItemCheckedChanging

The selectedIndexChanging event occurs before users changes the checked state of an item in RadCheckBoxList. This event can be canceled.

The event handler receives two parameters:

1. The instance of the loaded RadCheckBoxList control.

2. An eventArgs parameter of type Telerik.Web.UI.ButtonListCancelEventArgs, containing the following properties and methods:

   • get_item() - returns an instance of type Telerik.Web.UI.ButtonListItem (the clicked item).
   • get_cancel() - sets a bool value that indicates whether the event will be canceled. Setting true means the event will be canceled.
   • set_cancel() - returns a bool value that indicates whether the event was canceled. True means the event is canceled.

Example 1: Handling RadCheckBoxList OnItemCheckedChanging event.

ASP.NET

<script type="text/javascript">
	function OnItemCheckedChanging(sender, args) {
		var selectedLanguage = args.get_item().get_text();
		var toChange = !confirm("You checked on " + selectedLanguage + " language!");
		args.set_cancel(toChange);
	}
</script>

<telerik:RadCheckBoxList runat="server" ID="RadCheckBoxList1">
	<ClientEvents OnItemCheckedChanging="OnItemCheckedChanging" />
	<Items>
		<telerik:ButtonListItem Text="English" Selected="true" />
		<telerik:ButtonListItem Text="German" />
		<telerik:ButtonListItem Text="French" />
	</Items>
</telerik:RadCheckBoxList>

See Also

• CheckBoxList Object

• Events Overview

• OnLoad (load)

• OnItemLoad (itemLoad)

• OnItemClicking (itemClicking)

• OnItemClicked (itemClicked)

• OnSelectedIndexChanging (selectedIndexChanging)

• OnSelectedIndexChanged (selectedIndexChanged)

• OnItemMouseOver (itemMouseOver)

• OnItemMouseOut (itemMouseOut)