类的方法
所谓类的方法，也就是，这个方法会绑定到一个类上面，实例化一个instance的时候，这个方法不会再重新生成 一份，它只有访问类级别的变量
它用@classmethod标签来标注这是一个class method.
class Book(object): num = 10 # instance method, will be bound to an object def __init__(self, title, price): self.title = title self.price = price # class method, will not be bound to an object @classmethod def display(cls): print(" *******************************") print("this is a class method", cls.num) print("=============================== ") book = Book("Python Basic", 25) Book.display() book.display() print(" *******************************") print("<class method essence>") print(Book.display) print(book.display) print("=============================== ")
执行结果为：
******************************* this is a class method 10 =============================== ******************************* this is a class method 10 =============================== ******************************* <class method essence> <bound method type.display of <class '__main__.Book'>> <bound method type.display of <class '__main__.Book'>> ===============================