The event model stores object event properties. These properties are useful if you want to access values that are otherwise out of the scope of the events listed in the Show list within the Script Editor.
The event model controls the changes in a form that occur before, during, and after actions take place. These actions include dynamic form events, such as the point when the data and form design are merged but before pagination is applied, and also interactive form events, such as when a user updates the value of a field.
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About the event model