本文实例分析了python中类的一些方法,分享给大家供大家参考。具体分析如下:
先来看看下面这段代码:
class Super: def delegate(self): self.action() class Provider(Super): def action(self): print 'in Provider.action' x = Provider() x.delegate()
本文实例运行环境为Python2.7.6
运行结果如下:
in Provider.action
在Super类中定义delegate()方法,delegate中调用self.action,在Provider子类中实现action方法。子类调用父类的delegate方法时,实际是调用自己的action方法。。
总之一句话:
这里子类实现了父类delegate中所期望的action方法
再来看看下面这段代码:
class Super: def delegate(self): self.action() def method(self): print 'super method' class Inherit(Super): pass class Replace(Super): def method(self): print "replace method" class Extended(Super): def method(self): print 'in extended class' Super.method(self) print 'out extended class' class Provider(Super): def action(self): print 'in Provider.action' x = Inherit() x.method() print '*'*50 y = Replace() y.method() print '*'*50 z = Extended() z.method() print '*'*50 x = Provider() x.delegate()
运行结果如下:
super method ************************************************** replace method ************************************************** in extended class super method out extended class ************************************************** in Provider.action
分别继承父类的方法,替换父类的方法,扩展了父类的方法
Super类定义了delegate方法并期待子类实现action函数,Provider子类实现了action方法.
相信本文所述对大家Python程序设计的学习有一定的借鉴价值。

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