IEventTrigger interface (taskschd.h)
Represents a trigger that starts a task when a system event occurs.
Inheritance
The IEventTrigger interface inherits from the ITrigger interface.
Methods
The IEventTrigger interface has these methods.
| IEventTrigger::get_Delay Gets or sets a value that indicates the amount of time between when the event occurs and when the task is started. (Get) |
| IEventTrigger::get_Subscription Gets or sets a query string that identifies the event that fires the trigger. (Get) |
| IEventTrigger::get_ValueQueries Gets or sets a collection of named XPath queries. Each query in the collection is applied to the last matching event XML returned from the subscription query specified in the Subscription property. (Get) |
| IEventTrigger::put_Delay Gets or sets a value that indicates the amount of time between when the event occurs and when the task is started. (Put) |
| IEventTrigger::put_Subscription Gets or sets a query string that identifies the event that fires the trigger. (Put) |
| IEventTrigger::put_ValueQueries Gets or sets a collection of named XPath queries. Each query in the collection is applied to the last matching event XML returned from the subscription query specified in the Subscription property. (Put) |
Remarks
A maximum of 500 tasks with event subscriptions can be created. An event subscription that queries for a variety of events can be used to trigger a task that uses the same action in response to the events being logged.
When reading or writing your own XML for a task, an event trigger is specified using the EventTrigger element of the Task Scheduler schema.
Examples
For more information and example code for this interface, see Event Trigger Example (C++).
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps only] |
| Minimum supported server | Windows Server 2008 [desktop apps only] |
| Target Platform | Windows |
| Header | taskschd.h |