Assembly: System.Web.Extensions (in System.Web.Extensions.dll)
The UpdatePanel control. (You can define triggers declaratively by using the UpdatePanelTrigger Collection Editor dialog box in the designer or by using the <Triggers> element of the UpdatePanel control.) The collection includes AsyncPostBackTrigger and PostBackTrigger objects.property gets a collection of all the triggers that have been defined for the
Declarative triggers that are defined in thecollection are not tracked in view state.
When a control that is a naming container is used as a trigger, all its child controls that cause postback behave as triggers.
Available since 3.5