OnClientDropDownOpening

The OnClientDropDownOpening client-side event occurs right before the drop-down containerof RadAutoCompleteBox is opened.

The event handler receives two parameters:

1. The instance of RadAutoCompleteBox firing the event.

2. An eventArgs parameter containing the following two methods:

• get_cancel() - returns a boolean value indicating whether the event has been canceled.

• set_cancel(boolean) - cancels the event depending on the value passed as an argument.

This event is used in scenarios when operations need to be performed to RadAutoCompleteBox before opening the drop-down container, or when the opening need to be canceled.

<script type="text/javascript">
    function dropDownOpening(sender, eventArgs) {
        eventArgs.set_cancel(true);
        alert(eventArgs.get_cancel());
    }
</script>

<telerik:RadAutoCompleteBox RenderMode="Lightweight" runat="server" ID="RadAutoCompleteBox1" OnClientDropDownOpening="dropDownOpening"
    DataSourceID="SqlDataSource1" DataTextField="Name" DataValueField="ID">
</telerik:RadAutoCompleteBox>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:TelerikVSXConnectionString %>"
    SelectCommand="SELECT [ID], [CountryID], [Name] FROM [Cities]"></asp:SqlDataSource>

See Also

• Overview