📅  最后修改于: 2022-03-11 15:00:59.039000             🧑  作者: Mango
if let contex = (UIApplication.shared.delegate as? AppDelegate)?.persistentContainer.viewContext {}
(UIApplication.shared.delegate as? AppDelegate)?.
// saving context
(UIApplication.shared.delegate as? AppDelegate)?.saveContext()
if let context = (UIApplication.shared.delegate as? AppDelegate)?.persistentContainer.viewContext {