Python多態(tài)

2019-11-14 16:59:25

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供稿：網(wǎng)友

多態(tài):在編輯時無法確定狀態(tài)，在運行時才確定。由于Python為動態(tài)語言，參數(shù)類型沒定，所以本身即是多態(tài)的

1：由繼承實現(xiàn)多態(tài)

 1 class Animal: 2     def move(self): 3         PRint('Animal is moving') 4  5 class Dog: 6     def move(self): 7         print('Dog is running') 8  9 class Fish:10     def move(self):11         print('Fish is swimming')12 13 Animal().move()14 Dog().move()15 Fish().move()

結(jié)果：

Animal is moving
Dog is running
Fish is swimming

2：通過重載實現(xiàn)多態(tài)

1 #在子類中：2 3 class child:4     def start(self):5         print('....')6         super().start()7         print('......')

3：動態(tài)語言特性（參數(shù)類型不定）與鴨子模型

例子1：類實例為參數(shù)

class Animal:    def move(self):        print('Animal is moving')class Dog:    def move(self):        print('Dog is running')class Fish:    def move(self):        print('Fish is swimming')def move(obj):        #obj為實例參數(shù)    obj.move()            move(Animal())move(Dog())move(Fish())

----------------類作為參數(shù)-------------

class Moveable:    def move(self):        print('Move...')class MoveOnFeet(Moveable):    def move(self):        print("Move on Feet.")class MoveOnWheel(Moveable):    def move(self):        print("Move on Wheels.")        #-------------------------------------------------------------------        class MoveObj:    def set_move(self,moveable):                                #moveable為類        self.moveable = moveable()    def move(self):        self.moveable.move()                               #通過moveable實例調(diào)用到不同的類class Test:    def move(slef):        print("I'm Fly.")if __name__ == '__main__':    m = MoveObj()        m.set_move(Moveable)    m.move()        m.set_move(MoveOnFeet)    m.move()        m.set_move(MoveOnWheel)    m.move()        m.set_move(Test)    m.move()