如何在 python 的 super() 函数中指定使用哪个父类？答案

【问题标题】：How to specify which parent class to use in super( ) function in python?如何在 python 的 super() 函数中指定使用哪个父类？
【发布时间】：2021-12-12 09:28:30
【问题描述】：

我的目标：在调用 Parent2 类的 [identify] 方法的子类中创建名为 [identify2] 的方法。这必须使用 super() 关键字来完成。

我的问题：两个父类中的方法名称相同。但我只想涉及使用 super() 关键字的 parent2 类的方法。我该怎么办？

class Parent1:
  def identify(self):
    return "This method is called from Parent1"
    
class Parent2:
  def identify(self):
    return "This method is called from Parent2"
    
# declare child class here
class child(Parent1, Parent2):
  def identify(self):
    return "This method is called from Child"
  def identify2(self):
    super().identify()  # I want to call the method of Parent2 class, how?     
  
  
child_object = child()
#                                           Expected output:
print( child_object.identify() )        # This method is called from Child
print( child_object.identify2() )       # This method is called from Parent2

【问题讨论】：

标签： python oop inheritance overriding

【解决方案1】：

super 可以用类型和对象参数调用，参见documentation。 type 参数确定在 mro 顺序中的哪个类之后开始搜索该方法。在这种情况下，要获得Parent2 的方法，搜索应该在Parent1 之后开始：

class Parent1:
    def identify(self):
        return "This method is called from Parent1"
    
class Parent2:
    def identify(self):
        return "This method is called from Parent2"
    
# declare child class here
class Child(Parent1, Parent2):
    def identify(self):
        return "This method is called from Child"
    
    def identify2(self):
        return super(Parent1, self).identify()
  
  
child_object = Child()
#                                           Expected output:
print( child_object.identify() )        # This method is called from Child
print( child_object.identify2() )       # This method is called from Parent2

这给出了：

This method is called from Child
This method is called from Parent2

【讨论】：