forward="orginalEvent=targetId1/targetId2,targetEvent"

forward="originalEvent=${el-expr},targetEvent"

forward="targetEvent"

It is used to forward an event, that is targeting a specific component, to another component in another event name. It is called the forward condition.

The original event is optional. If it is omitted, onClick is assumed. Similarly, the target ID is also optional. If omitted, the space owner is assumed.

If you want to forward several events, you can specify these conditions in the forward attribute by separating them with the comma (,):

<textbox forward="onChanging=onUpdating, onChange=some.onUpdate"/>