Question

我希望在SuperClass中打印所有子类，并在子类中打印所有超类：

class SuperClass():
    def Print(self):
        print('my sub classes are : ')
        #print all childs

class Sub1(SuperClass,...):
    def Print(self):
        print('My parents are :')
        #print all SuperClasses

class Sub2(SuperClass,...):
    def Print(self):
        print('My parents are :')
        #print all SuperClasses

SuperClass有Print可以打印所有继承的类，而Sub有Print方法可以打印所有的SuperClasses。怎么做？

Answer 1

Python类有三个有用的属性：

class.__subclasses__();返回类的所有子类的方法。
class.__bases__，是当前班级的直接父类的元组。
class.__mro__，在当前类层次结构中包含所有类的元组。在该元组中查找当前的类对象，后面的所有内容都是父类，直接或间接。

使用以下内容：

class SuperClass(object):
    def print(self):
        print('my sub classes are:', ', '.join([
            cls.__name__ for cls in type(self).__subclasses__()]))

class Sub1(SuperClass):
    def print(self):
        print('My direct parents are:', ', '.join([
            cls.__name__ for cls in type(self).__bases__]))
        all_parents = type(self).__mro__
        all_parents = all_parents[all_parents.index(Sub1) + 1:]
        print('All my parents are:', ', '.join([
            cls.__name__ for cls in all_parents]))

演示：

>>> SuperClass().print()
my sub classes are: Sub1
>>> Sub1().print()
My direct parents are: SuperClass
All my parents are: SuperClass, object

打印SuperClass中的所有SubClass和SubClass中的所有SuperClass

1 个答案: