python 的继承和多态

继承
子类可以继承父类的方法
多态
不同子类不仅继承父类的相同方法，还可以定义自己的方法

class Anim():    def run(self):        print 'Anim is runing....'class Dog(Anim):    def run(self):        print 'dog is runing....'    def eat(self):        pring 'dog us rating....'class Cat(Anim):    pass    #def run(self):        #print 'cat is runing....'a=Anim()d=Dog()cat=Cat()a.run()d.run()   #使用自定义的run方法cat.run() #继承父类的run方法，可直接调用多态的其中用途def tw(cl):    cl.run()    cl.run()    cl.run()tw(Anim())#Anim is runing....#Anim is runing....#Anim is runing....tw(Dog())#dog is runting....#dog is runting....#dog is runting....tw(Cat())#cat is runing....#cat is runing....#cat is runing....

type() 判断对象类型
isinstance()判断class类类型
dir()获取属性所有的属性和方法

hasattr()判断对象是否存在弄个属性
setattr()设置一个新的属性
getattr()获取某个属性

例

class Student():    def __init__(self,name,score):        self.name=name        self.score=scoreS=Student('ruan',90)setattr(S,'test','ttt')print hasattr(S,'test')#trueprint getattr(S,'test')#ttt