GETATTR,DELATTR,SETATTR与GETITEM,SETITEM,DELITEM区别

Posted 2021-01-06 konglinqingfeng

class Foo:
    def __getitem__(self, item):
        print('getitem', item)
        return self.__dict__[item]

    def __setitem__(self, key, value):
        print('setitem')
        self.__dict__[key] = value

    def __delitem__(self, key):
        print('delitem')
        self.__dict__.pop(key)

f1 = Foo()
# f1.name='alex'
f1['name']='alex'
f1['age']='222'
print(f1.__dict__)

# del f1.name
# print(f1.__dict__)
#没有触发打印,因为通过对象.属性的方式触发的是__getattr__,__delattr__,__setattr__
#通过对象['属性']触发__getitem__,__setitem__,__delitem__

del f1['name']
print(f1.__dict__)

# f1['age']
print(f1['age'])