begin(_:with:)
Sets up state information before the start of a given entity mapping.
Declaration
func begin(_ mapping: NSEntityMapping, with manager: NSMigrationManager) throwsParameters
- mapping:
The mapping object in use.
- manager:
The migration manager performing the migration.
Discussion
This method is the precursor to the creation stage. In a custom class, you can implement this method to set up any state information that will be useful for the duration of the migration.