Question

我已经获得了一个继承函数的类。

class shape(object):
    '''Shape is an base class, which is largely intended to be abstract, that
    is only used as a parent class to other classes wich define specific shapes
    and inherit the shape class' fuctions getArea() and printArea()
    '''

    def __init__(self):
        '''constructor function for the shape class
        '''
        self.area = None
        self.name = "shape"

    def getArea(self):
        '''returns the area of the shape, which is defined in the constructor
        '''
        return self.area

    def printArea(self):
        '''prints a statement identifying the shape by its name and giving the
        area of the shape. Returns None.
        '''
        print "The area of this " + self.name + " is: " + str(self.area)
        return None

我必须与之合作，因此无法改变。然后，我所做的是：

class circle(shape):
    """A new class 'circle' that will inherit functions from the class 'shape'.
    """

    def __init__(self, diameter):
        """A constructor function for the circle class.
        """
        self.area = math.pi * (diameter ** 2 / 4.0)
        self.name = circle

c = circle(10)

print c.getArea()
print c.printArea()

getArea部分工作正常，但printArea没有。我收到了标题中的错误消息。

Answer 1

self.name必须是"circle"，而不是circle。

不能连接＆＃39; str＆＃39;和＆＃39;键入＆＃39;对象（初学者）

1 个答案: