重新梳理Python基礎（11）

1. python中的繼承

class Parent(object):    def override(self):        print "PARENT override()"    def implicit(self):        print "PARENT implicit()"    def altered(self):        print "PARENT altered()"class Child(Parent):    def override(self):        print "CHILD override()"    def altered(self):        print "CHILD, BEFORE PARENT altered()"        super(Child, self).altered() #注意super的用法！！！！        print "CHILD, AFTER PARENT altered()"dad = Parent()son = Child()dad.implicit()son.implicit()dad.override()son.override()dad.altered()son.altered()

python可以多重繼承，即一個class可以有多個父類。

class Son(Dad, Mum):    pass

這時，當調用super(Son, self).***()的時候，會看Dad裡有沒有這個方法，如果有，就不調用Mum裡的了，如果沒有，才查看Mum裡有沒有，看下面的代碼：

class Parent(object):    def override(self):        print "PARENT override"    def implicit(self):        print "PARENT implicit"    def altered(self):        print "PARENT altered"class Mum(object):    def altered1(self):        print "MUM, altered."class Child(Mum, Parent):    def override(self):        print "CHILD override"    def altered(self):        print "CHILD, BEFORE PARENT altered()"        super(Child, self).altered1()        super(Child, self).altered()        print "CHILD, AFTER PARENT altered()"dad = Parent()son = Child()dad.implicit()son.implicit()dad.override()son.override()dad.altered()son.altered()

輸出結果：

E:\SkyDrive\python\the hard way to learn python>python ex44_4.pyPARENT implicitPARENT implicitPARENT overrideCHILD overridePARENT alteredCHILD, BEFORE PARENT altered()MUM, altered.PARENT alteredCHILD, AFTER PARENT altered()