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HomeBackend DevelopmentPython Tutorialpython中类的一些方法分析

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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