Python类中的property的用法

class Duck():
    def __init__(self, input_name):
        self.hidden_name = input_name

    def get_name(self):
        print('inside the getter')
        return self.hidden_name

    def set_name(self, input_name):
        print('inside the setter')
        self.hidden_name = input_name

    name = property(get_name, set_name)  # property将get_name转换为getter方法，set_name为setter方法


a = Duck('hhh')
print(a.name)  # 会自动调用get_name,打印inside the getter并返回hhh
print(a.hidden_name)  # 仍然可以直接访问hidden_name


class Duck():
    def __init__(self, input_name):
        self.hidden_name = input_name

    @property
    def name2(self):  # 另外一种设置getter方法的方法
        print('inside the getter')
        return self.hidden_name

    @name2.setter
    def set(self, input_name):  # setter方法
        print('inside the setter')
        self.hidden_name = input_name


a = Duck('hhh')
print(a.name2)


class Circle():
    def __init__(self, radius):
        self.radius = radius

    @property
    def diameter(self):  # 将方法转换为属性
        return 2 * self.radius


c = Circle(5)
print(c.diameter)  # 返回10
c.radius = 7
print(c.diameter)  # 可动态计算，返回14
try:
    c.diameter = 15  # 因为没有在类中指定setter方法@diameter.setter，所以无法从外部设置
except Exception as exc:
    print(exc)


class Circle():
    def __init__(self, radius):
        self.radius = radius
        self.diameter = 2 * self.radius


c = Circle(5)
print(c.diameter)  # 返回10
c.radius = 7
print(c.diameter)  # 不可动态计算，返回10
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参考资料：《Python语言及其应用》【美】卢巴诺维奇 著