python - TypeError - Python 中的类

Question

我是 Python 的初学者，刚开始学习类。我确定这可能是非常基本的东西，但为什么这段代码:

class Television():
    def __init__(self):
        print('Welcome your TV.')
        self.volume = 10
        self.channel = 1
    def channel(self, channel):
        self.channel = input('Pick a channel: ')
        print('You are on channel ' + self.channel)
    def volume_up(self, amount):
        self.amount = ('Increase the volume by: ')
        self.volume += self.amount
        print('The volume is now ' + self.volume)
    def volume_down(self, amount):
        self.amount = ('Decrease the volume by: ')
        self.volume -= self.amount
        print('The volume is now ' + self.volume)
myTele = Television()
myTele.channel()
myTele.volume_up()
myTele.volume_down()

产生以下错误:

TypeError: 'int' object is not callable, Line 18

编辑:我将代码更改为:

class Television():
    def __init__(self, volume = 10, channel = 1):
        print('Welcome your TV.')
        self.volume = volume
        self.channel = channel
    def change(self, channel):
        self.channel = input('Pick a channel: ')
        print('You are on channel ' + self.channel)
    def volume_up(self, amount):
        self.amount = int(input('Increase the volume by: '))
        self.volume += self.amount
        print('The volume is now ' + str(self.volume))
    def volume_down(self, amount):
        self.amount = int(input('Decrease the volume by: '))
        self.volume -= self.amount
        print('The volume is now ' + str(self.volume))
myTele = Television()
myTele.change()
myTele.volume_up()
myTele.volume_down()

但它返回:

TypeError: change() missing 1 required positional argument: 'channel'

再次声明，这是来自刚开始类的人，所以如果我做错了一些明显的错误，请不要太苛刻。谢谢。

Answer 1

您在 __init__ 中分配一个 channel 属性:

self.channel = 1

这会隐藏类中的 channel() 方法。重命名属性或方法。

实例的属性胜过类的属性(数据描述符除外；想想 property)。来自Class definitions documentation :

Variables defined in the class definition are class attributes; they are shared by instances. Instance attributes can be set in a method with self.name = value. Both class and instance attributes are accessible through the notation “self.name”, and an instance attribute hides a class attribute with the same name when accessed in this way.

您的方法还需要一个您未在示例中传递的参数，但我想您接下来会自己解决这个问题。