Event Handlers are used to link process flows to entities or applications. In this case, since the process flow is executing validation logic for the Employees entity, we need to create an Event Handler for the Employees entity using either the BeforeValidate or AfterValidate event definition. For BeforeValidate, the system will run the process flow before executing the standard GE validation. For AfterValidate, the system will run the process flow after executing the standard GE validation. We can link the event handler to either event but for the sake of this example, we will link it to the AfterValidate event (so it occurs after the standard validation).
Setting Up the Event Handler
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