對象屬性查找順序

目錄

• 1、屬性查找

1、屬性查找

• 先從對象本身的名稱空間找，沒有則去類中找，若是類也沒有則報錯

class OldboyStudent:
    school = 'oldboy'
    count = 0
    aa = 10

    def __init__(self, x, y, z):  #會在調用類時自動觸發
        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

• 因爲上述修改的是類屬性，類屬性的count已經被修改成3，因此其餘實例的count都爲3

print(stu1.count)

3

print(stu2.count)

3

print(stu3.count)

3

• 因爲aa是私有屬性，所以stu們都會用本身私有的aa，不會用類的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}