先来看一下一个常见的Python类的定义:
class Person(object): name = None age = None def __init__(self,name,age): self.name = name self.age = age if __name__=="__main__": p = Person(name='jianglegege',age=16) print(p.name,p.age) # jianglegege 16
来一个需求:
每一个person实例都要有一个sid属性用来记录社保号
写法 1): 直接改Person类
class Person(object): name = None age = None sid = None def __init__(self,name,age,sid): self.name = name self.age = age self.sid = sid
写法 2):创建完实例后单独为实例设置sid属性
class Person(object): name = None age = None def __init__(self,name,age): self.name = name self.age = age if __name__=="__main__": p = Person(name='jianglegege',age=16) p.sid = '9527' print(p.name,p.age,p.sid)
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