继承（第十三章）

class 类名(被继承的类):
  .....

>>> class Parent:
...     def hello(self):
...             print("正在调用父类方法")
...
>>> class Child(hello):
...     pass
...
>>> p = Parent()
>>> p.hello()
正在调用父类方法
>>> c = Child()
>>> c.hello()
正在调用父类方法
>>>

import random as r#调用


class Fish:#一个类
    def __init__(self):#还记得上一章的魔法方法吗__init__可以实实例化对像来代入参数
      self.x = r.randint(0,10)
      self.y = r.randint(0,10)

    def move(self):
        self.x -=1
        print("我的位置是",self.x,self.y)
    def goldfish(Fish):
        pass

    def carp(Fish):
        pass

    def Salmon(Fish):
        pass
class Shark(Fish):#定义鲨鱼，一个傻鲨鱼
    def __init__(self):#这里会讲到调用未绑定的父类方法
        self.hungry = True
    def eat(self):
        if self.hungry:
            print("我是个大吃货")
            self.hungry = False
        else:
            print("饱了，不吃了")

>>> fish = Fish()
>>> fish.move()
我的位置是 2 7
>>> shark = Shark()
>>> shark.move()
Traceback (most recent call last):
  File "<pyshell#94>", line 1, in <module>
    shark.move()
  File "C:/Users/Administrator/Desktop/魔法方法.py", line 10, in move
    self.x -=1
AttributeError: 'Shark' object has no attribute 'x'
>>> 

class Shark(Fish):
    def __init__(self):
        Fish.__init__(self)
        self.hungry = True
    def eat(self):
        if self.hungry:
            print("我是个大吃货")
            self.hungry = False
        else:
            print("饱了，不吃了")

class Shark(Fish):
    def __init__(self):
        super().__init__()
        self.hungry = True
    def eat(self):
        if self.hungry:
            print("我是个大吃货")
            self.hungry = False
        else:
            print("饱了，不吃了")

>>> shark = Shark()
>>> shark.move()
我的位置是 4 9

class 类名(父类1，父类2，父类3......)
.......

class Base1:
    def fool(self):
        print("我是fool,我在Basel中")

class Base2:
    def foo2(self):
        print("我是foo2,我在Basel中")

class Cat(Base1,Base2):
    pass

>>> cat = Cat()
>>> cat.fool()
我是fool,我在Basel中
>>> cat.foo2()
我是foo2,我在Basel中
>>>