iOS: Delete ALL Core Data Swift

Question

I am a little confused as to how to delete all core data in swift. I have created a button with an IBAction linked. On the click of the button I have the follow

Answer 1

Swift 5.1

Most of the posts here suggests to create a function to delete all entities by name and then delete all your entities by name. like so :

resetEntity(named: "MyEntity1")
resetEntity(named: "MyEntity2")
resetEntity(named: "MyEntity3")
...

But if the real question is how to clean ALL CoreData entity in one go, I suggest you loop over entity names:

// Supposing this is a CoreDataController/CoreDataStack class where you have access to `viewContext` and `persistantContainer`
// Otherwise just pass the `persistantContainer` as a parameter, from which you can also retrieve the `viewContext` 
func resetAllCoreData() {

     // get all entities and loop over them
     let entityNames = self.persistentContainer.managedObjectModel.entities.map({ $0.name!})
     entityNames.forEach { [weak self] entityName in   
        let deleteFetch = NSFetchRequest(entityName: entityName)
        let deleteRequest = NSBatchDeleteRequest(fetchRequest: deleteFetch)

        do {
            try self?.context.execute(deleteRequest)
            try self?.context.save()
        } catch {
            // error
        }
    }
}

Hope this can help