如何在python中使用子类修改超类的属性？

Question

我有一个类 Rectangle

class Rectangle:
    def __init__(self, width, height):
        self.width = width
        self.height = height
        
    def set_width(self, width):
        self.width = width
        
    def set_height(self, height):
        self.height = height
        
    def get_area(self):
        return self.width * self.height
    
    def get_perimeter(self):
        return self.width*2 + self.height*2
    
    def get_diagonal(self):
        return (self.width ** 2 + self.height ** 2) ** .5
    
    def get_picture(self):
        picture = str()
        if self.width >= 50 | self.height >= 50:
            return "Too big for picture."
        
        for height in range(self.height):
            picture += "*"*self.width+"\n"
            
        return picture
    
    def __repr__(self):
        return f"Rectangle(width={self.width}, height={self.height})"

它的子类 Square

class Square(Rectangle):
    def __init__(self, length):
        super().__init__(length, length)
        self.length = length
    
    def set_side(self, length):
        super().__init__(length, length)
        self.length = length
    
    def set_width(self, length):
        super().__init__(length, length)
        self.length = length        
        
    def set_height(self, length):
        super().__init__(length, length)
        self.length = length
        
    def __repr__(self):
        return f"Square(side={self.length})"

每次我想改变值时，我都会调用 super()。init()。

我想要的不是在 Square 类中明确定义 set_height 和 set_width ，有没有一种方法可以通过调用 set side 将高度和宽度设置为 length 并且 str repr 也应该显示新的 set 边？ 另外，我觉得有比我做的更好的方法来做到这一点。

Answer 1

这是一个类似的例子：

class Rectangle : 

   def __init__(self,length,width):
        self.length = length 
        self.width = width  
       

class Square(Rectangle) : 
    
   def __init__(self, length, width):
       super().__init__(length, width)  

   def area(self): 
       return self.length*self.width 


class Cube(Rectangle): 

   def __init__(self,length, width,height):
       super().__init__(length, width)  
       self.height = height  
       
   def volume(self): 
       return self.length*self.width*self.height

square = Square(3,3) 
cube  = Cube(3,3,3) 

print(square.area()) 
print(cube.volume())

Answer 2

所以，有趣的是，我现在正在与 freecodecamp 做同一个项目。然而，我走了一条与此不同的路线。您不必像那样将所有这些方法添加到子类中。您可以在 Square 类中定义边。我将分享我到目前为止所做的事情。现在这还远未完成。我喜欢降低功能，然后简化并使其更清洁。我正在研究 get_amount_inside() 方法，并且正在寻找如何从子类中提取属性以在超类中使用。

class Rectangle:

    def __init__(self, width=None, height=None):
        self.height = height
        self.width = width
        self.area = None
        self.perimeter = None
        self.diagonal = None
        self.side = None

    def set_attributes(self, new_width=None, new_height=None):
        self.side = new_width or new_height
        self.width = new_width
        self.height = new_height
        return self.width, self.height

     def set_width(self, new_width):
        self.width = new_width
        return self.width

    def set_height(self, new_height):
        self.height = new_height
        return self.height

    def get_area(self):
        if self.side is not None:
            self.area = (self.side ** 2)
            return self.area
        else:
            self.area = (self.width * self.height)
            return self.area

    def get_perimeter(self):
        if self.side is not None:
            self.perimeter = (self.side * 4)
            self.perimeter = ((2 * self.height) + (2 * self.width))
            return self.perimeter
        else:
            self.perimeter = ((2 * self.height) + (2 * self.width))
            return self.perimeter

    def get_diagonal(self):
        if self.side is not None:
            self.diagonal = ((self.side ** 2) * 2) ** 0.5
            return self.diagonal
        else:
            self.diagonal = (self.height ** 2 + self.width ** 2)**0.5
            return self.diagonal

    def __repr__(self):
        self.get_area()
        self.get_perimeter()
        self.get_diagonal()
        rectangle = ["Rectangle" + "(width=" + str(self.width), ", height=" + str(self.height) + ")"]
        return "".join(rectangle)


class Square(Rectangle):

    def __init__(self, side):
        self.side = side

    def set_side(self, new_side):
        self.side = new_side
        return self.side

    def __repr__(self):
        square = ["Square" + "(side=" + str(self.side) + ")"]
        return "".join(square)

我对这个项目的问题与你的完全不同。我完全忘记了 f"" 格式化方法，所以我很高兴我点击了这个链接。 -ZichKoding 是我在 Repl.it 上的名字

Answer 3

    class Rectangle:
        def __init__(self, width, height):
            self.width = width
            self.height = height
            
        def set_width(self, width):
            self.width = width
            
        def set_height(self, height):
            self.height = height
            
        def get_area(self):
            return self.width * self.height
        
        def get_perimeter(self):
            return self.width*2 + self.height*2
        
        def get_diagonal(self):
            return (self.width ** 2 + self.height ** 2) ** .5
        
        def get_picture(self):
            picture = str()
            if self.width >= 50 | self.height >= 50:
                return "Too big for picture."
            
            for height in range(self.height):
                picture += "*"*self.width+"\n"
                
            return picture
        
        def __repr__(self):
            return f"Rectangle(width={self.width}, height={self.height})"
    
    
    
    class Square(Rectangle):
        def __init__(self, length):
            super().__init__(length, length)
            self.length = length
        
        def set_side(self, length):
            super().__init__(length, length)
            self.length = length
        
        def set_width(self, length):
            # super().__init__(length, length)
            # self.length = length     
            self.set_side(length)   
            
        def set_height(self, length):
            # super().__init__(length, length)
            # self.length = length
            self.set_side(length)   
    
            
        def __repr__(self):
            return f"Square(side={self.length})"
    
    
    
    # r = Rectangle(20, 20)
    s = Square(20)
    
    # print(r)
    print(s)
    s.set_width(60)
    print(s)