Question

我想从TwoDim类开始并计算体积，而无需重复定义长度和宽度，也无需创建TwoDim实例，而是直接创建ThreeDim。

class TwoDim():
    def __init__(self, length, width):
        self.length = length
        self.width = width
        self.square = self.length * self.width

class ThreeDim(TwoDim):
    def __init__(self, height):
        self.height = height
        self.volume = self.square * self.height

我尝试像这样的方法，但仍然无法正常工作。

class TwoDim(): 
    def __init__(self, length, width): 
        self.length = length 
        self.width = width 
        self.square = self.length * self.width 

class ThreeDim(TwoDim): 
    def __init__(self, length, width, height): 
        super().__init__(self, length, width, height) 
        self.height = height 
        self.volume = self.square * self.height 

block = ThreeDim(length = 10, width = 5, height = 4)

Answer 1

Python 3：

class ThreeDim(TwoDim):
    def __init__(self, length, width, height):
        super().__init__(length, width)
        self.height = height
        self.volume = self.square * self.height

Python 2：

class ThreeDim(TwoDim, object):
    def __init__(self, length, width, height):
        super(ThreeDim, self).__init__(length, width)
        self.height = height
        self.volume = self.square * self.height

或：

class TwoDim(object):
    def __init__(self, length, width):
        self.length = length
        self.width = width
        self.square = self.length * self.width

class ThreeDim(TwoDim):
    def __init__(self, length, width, height):
        super(ThreeDim, self).__init__(length, width)
        self.height = height
        self.volume = self.square * self.height

（{classes need to inherit from object to use super()，这就是python3语法更容易的原因之一。）

别忘了TwoDim上的self参数：

class TwoDim():
    def __init__(self, length, width):
        self.length = length
        self.width = width
        self.square = self.length * self.width

Python继承为子代添加新的init

1 个答案: