117 对象的属性查找顺序

 

 

一、属性查找

  • 先从对象自己的名称空间找,没有则去类中找,如果类也没有则报错
class OldboyStudent:
    school = 'oldboy'
    count = 0
    aa = 10

    def __init__(self, x, y, z):  #会在调用类时自动触发
        self.name = x  # stu1.name='耗哥'
        self.age = y  # stu1.age=18
        self.sex = z  # stu1.sex='male'
        OldboyStudent.count += 1
        #         self.count += 5
        self.aa = 1

    def choose_course(self):
        print('is choosing course')
print(OldboyStudent.count)
0
stu1 = OldboyStudent('nick', 18, 'male')
print(stu1.count)
1
stu2 = OldboyStudent('sean', 17, 'male')
print(stu2.count)
2
stu3 = OldboyStudent('tank', 19, 'female')
print(stu3.count)
3
print(OldboyStudent.count)
3
print(stu1.name)
nick
  • 由于上述修改的是类属性,类属性的count已经被修改为3,所以其他实例的count都为3
print(stu1.count)
3
print(stu2.count)
3
print(stu3.count)
3
  • 由于aa是私有属性,因此stu们都会用自己私有的aa,不会用类的aa
print(stu1.__dict__)
{'name': 'nick', 'age': 18, 'sex': 'male', 'aa': 1}
print(stu2.__dict__)
{'name': 'sean', 'age': 17, 'sex': 'male', 'aa': 1}
print(stu3.__dict__)
{'name': 'tank', 'age': 19, 'sex': 'female', 'aa': 1}
posted @ 2019-11-16 18:21  ABDM  阅读(163)  评论(0编辑  收藏  举报