反射和类内置方法

Posted 2021-01-06 hhsh

# class Teacher:
#     dic = {‘查看学生信息‘: ‘show_student‘, ‘查看老师‘: ‘show_teacher‘}
#
#     def show_student(self):
#         print(‘show student‘)
#
#     def show_teacher(self):
#         print(‘show teacher‘)
#
#     @classmethod
#     def func(cls):
#         print(‘func‘)
#
# chen = Teacher()
# key = input(‘input:‘)
# if hasattr(chen, Teacher.dic[key]):
#     func = getattr(chen, Teacher.dic[key])
#     print(func)

# class A:
#     name = ‘1‘
#
#     def func(self):
#         print(‘aaaaaa‘)
#
# a = A()
# if hasattr(a, ‘name‘):
#     ret1 = getattr(a, ‘name‘)
#     ret2 = getattr(a, ‘func‘)
#     print(ret1)
#     ret2()

class A:
    pass
    def __str__(self):
        return ‘>>str‘

    def __repr__(self):
        return ‘repr‘

# %s print()和str(obj)都是调用__str__
# repr(obj)和%r都是调用__repr__
# 如果本类无__str__, 就实现__repr__, repr是str的备胎，但str不能做repr的备胎

a = A()
print(a)    # 打印对象就是调用__str__方法,如果本类无实现str方法，会调用object的__str__（内存地址）
print(‘%s‘ %a)
print(str(a))

print(repr(a))
print(‘%r‘%a)

# class A:
#     def __init__(self, name):
#         self.name = name
#
#     def __call__(self):
#         print(self.__dict__)
#
# a = A(‘chen‘)()