Applies To:

Timer

Description

This property specifies one-off behaviour for a Timer object. It has the value 0, 1 or 2.

Setting FireOnce to 1, will cause the Timer to generate a single event and no more unless it is reset. After generating the single event, FireOnce is automatically set to 2 and this change occurs prior to the invocation of a callback function.

Setting FireOnce to 2 will cause the Timer to behave as if it has already raised its single event.

FireOnce honours the value of the Active property but does not change it. So setting FireOnce to 1 when Active is 0 will not immediately cause an event. If Active is subsequently set to 1, the single Timer event will then occur.