python - 基类方法的重写方法调用如何工作？

Question

根据docs on inheritance :

Derived classes may override methods of their base classes. Because methods have no special privileges when calling other methods of the same object, a method of a base class that calls another method defined in the same base class may end up calling a method of a derived class that overrides it.

这是怎么发生的？有人可以用一个简单的例子来说明这个概念吗？

Answer 1

这是您要求的示例。这会打印出 chocolate。

class Base:
    def foo(self):
        print("foo")
    def bar(self):
        self.foo()

class Derived(Base):
    def foo(self):
        print("chocolate")

d = Derived()
d.bar()  # prints "chocolate"

字符串 chocolate 被打印而不是 foo 因为 Derived 覆盖了 foo() 函数。尽管 bar() 是在 Base 中定义的，但它最终还是调用了 foo() 的 Derived 实现Base 实现。