Python-属性描叙符协议ORM实现原理依据- __set__ __get__ __delete__

class CheckString:
    def __init__(self, variable_type):
        self.variable_type = variable_type

    def __set__(self, instance, value):
        print(‘__set__:‘, value)
        self.value = "error：类型错误"
        if self.variable_type == ‘str‘:
            self.value = value if isinstance(value, str) else "error：类型错误"

    def __get__(self, instance, owner):
        print("__get__")
        return self.value
        pass

    def __delete__(self, instance):
        pass


class InfoModel:
    name = CheckString(variable_type=‘str‘)


if __name__ == ‘__main__‘:
    info = InfoModel()
    info.name = "北门吹雪"
    print(info.name)