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pyclass-繼承

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接下來我們開始玩繼承吧

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class 子類 (父類)

繼承(Inheritance)

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class car:
    def __init__(self):
        self.color = "balck"
    def drive(self):
        print("The driver is Sam")

class Airplane(car):
    def acc(self):
        print("acc is already")

class buff(car):
    def button(self):
        print("touch")
        
mr = car()
mr.drive()
print("The Car is " + mr.color)

test = Airplane()
test.acc()

# The Car is balck
# The driver is Sam
# acc is already

使用issubclass()來判斷是否為子類別

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print(issubclass(Airplane, car)) 
# True

方法覆寫(Method Overriding)

當子類別中定義了和父類別同名的方法(Method)，這時候子類別的物件(Object)呼叫這個同名方法時，其中的實作內容將會覆蓋掉父類別的同名方法，這就叫做方法覆寫(Method Overriding)

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class car:
    def drive(self):
        print("The driver is Sam")

# class Airplane(car):
#     def acc(self):
#         print("acc is already")

class buff(car):
    def tes(self):
        super().drive()
        print("touch")
        
mr = car()
mr.drive()
test = buff()
test.tes()

# The driver is Sam
# The driver is Sam
# touch

多層繼承(Multi-Level Inheritance)

如果……

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class car:
    def drive(self):
        print("The driver is Sam")

class Airplane(car):
    def acc(self):
        print("acc is already")

class buff(Airplane):
    def tes(self):
        super().drive()
        print("touch")

這樣就會變得互相牽引，不過以上面為例似乎不明顯就是了

多重繼承(Multiple Inheritance)

趕鴨子上架

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class animal:
    def eat(self):
        print("eat fish")

class bird:
    def eat(self):
        print("eat bird")

class duck(animal, bird):
    pass

me = duck()
me.eat()
# 這邊會出現
# eat fish
# 如果我將animal與bird的順序交換，則會出現eat bird

為了避免這個問題，我們需要將上面2個class內部修正一下

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class animal:
    def eat(self):
        print("eat fish")

class bird:
    def wing(self):
        print("eat bird")

class duck(animal, bird):
    pass
# ....

這樣就ok了喔~~