// 1.創(chuàng)建類
class Student {
var book : Book?
deinit {
print("Student -- deinit")
}
}
class Book {
var owner : Student?
deinit {
print("Book -- deinit")
}
}
// 2.創(chuàng)建對(duì)象
var stu : Student? = Student()
var book : Book? = Book()
// 3.相互引用
stu?.book = book
book?.owner = stu
// 4.對(duì)象置nil
stu = nil
book = nil
// 1.創(chuàng)建類
class Student {
weak var book : Book?
// unowned var book : Book = Book()
deinit {
print("Student -- deinit")
}
}
class Book {
var owner : Student?
deinit {
print("Book -- deinit")
}
}
// 2.創(chuàng)建對(duì)象
var stu : Student? = Student()
var book : Book? = Book()
// 3.相互引用
stu?.book = book!
book?.owner = stu
// 4.對(duì)象置nil
stu = nil
book = nil
