Python多继承案例如何继承多父类

wen python案例 2026-06-30 224

Python多继承案例

基本语法

class Father:
    def __init__(self, name):
        self.name = name
        print(f"Father __init__: {self.name}")
    def skill(self):
        return "会修车"
    def hobby(self):
        return "喜欢钓鱼"
class Mother:
    def __init__(self, name):
        self.name = name
        print(f"Mother __init__: {self.name}")
    def skill(self):
        return "会做饭"
    def hobby(self):
        return "喜欢种花"
# 多继承：同时继承Father和Mother
class Child(Father, Mother):
    def __init__(self, name, age):
        # 注意：多继承时只调用第一个父类的__init__
        super().__init__(name)
        self.age = age
        print(f"Child __init__: {self.name}, {self.age}")
    def show_all_skills(self):
        # 演示方法解析顺序（MRO）
        print(f"技能：{self.skill()}")  # 调用Father的skill
        print(f"爱好：{self.hobby()}")  # 调用Father的hobby
# 使用示例
child = Child("小明", 10)
child.show_all_skills()
print(f"Child的MRO顺序：{Child.__mro__}")

MRO（方法解析顺序）示例

class A:
    def method(self):
        return "A"
class B(A):
    def method(self):
        return "B"
class C(A):
    def method(self):
        return "C"
class D(B, C):
    def method(self):
        return "D"
# 查看MRO
print(D.__mro__)
# 输出：(<class '__main__.D'>, <class '__main__.B'>, 
#        <class '__main__.C'>, <class '__main__.A'>, <class 'object'>)
d = D()
print(d.method())  # 输出：D

钻石继承（菱形继承）问题

class Animal:
    def __init__(self, name):
        print("Animal __init__")
        self.name = name
class Mammal(Animal):
    def __init__(self, name, has_fur=True):
        print("Mammal __init__")
        super().__init__(name)
        self.has_fur = has_fur
class Bird(Animal):
    def __init__(self, name, can_fly=True):
        print("Bird __init__")
        super().__init__(name)
        self.can_fly = can_fly
class Bat(Mammal, Bird):  # 会飞的哺乳动物
    def __init__(self, name):
        print("Bat __init__")
        super().__init__(name)
# 测试钻石继承
bat = Bat("蝙蝠")
print(f"名字：{bat.name}")
print(f"有毛皮：{bat.has_fur}")
print(f"会飞：{bat.can_fly}")
print(f"Bat的MRO：{Bat.__mro__}")

使用super()正确处理多继承

class Base1:
    def __init__(self):
        print("Base1 __init__")
        super().__init__()
class Base2:
    def __init__(self):
        print("Base2 __init__")
        super().__init__()
class MultiChild(Base1, Base2):
    def __init__(self):
        print("MultiChild __init__")
        super().__init__()
# 测试super()链式调用
mc = MultiChild()
print(f"MRO: {MultiChild.__mro__}")

实际应用示例：混合类

class LogMixin:
    """日志功能混合类"""
    def log(self, message):
        print(f"[{self.__class__.__name__}] {message}")
class TimeMixin:
    """时间处理混合类"""
    def get_timestamp(self):
        from datetime import datetime
        return datetime.now().strftime("%Y-%m-%d %H:%M:%S")
class User(LogMixin, TimeMixin):
    """用户类继承多个功能混合类"""
    def __init__(self, name):
        self.name = name
    def save(self):
        self.log(f"保存用户：{self.name}")
        print(f"时间戳：{self.get_timestamp()}")
# 使用示例
user = User("张三")
user.save()

方法重写与super()调用

class FileHandler:
    def open_file(self, filename):
        print(f"FileHandler: 打开文件 {filename}")
    def close_file(self):
        print("FileHandler: 关闭文件")
class EncryptedFileHandler(FileHandler):
    def open_file(self, filename):
        print("EncryptedFileHandler: 解密")
        super().open_file(filename)  # 调用父类方法
    def close_file(self):
        super().close_file()  # 调用父类方法
        print("EncryptedFileHandler: 加密")
class CompressedFileHandler(FileHandler):
    def open_file(self, filename):
        print("CompressedFileHandler: 解压")
        super().open_file(filename)
    def close_file(self):
        super().close_file()
        print("CompressedFileHandler: 压缩")
# 多重继承组合
class SuperFileHandler(EncryptedFileHandler, CompressedFileHandler):
    def open_file(self, filename):
        print("SuperFileHandler: 开始处理")
        super().open_file(filename)
    def close_file(self):
        super().close_file()
        print("SuperFileHandler: 处理完成")
# 测试
handler = SuperFileHandler()
handler.open_file("test.txt")
print("---")
handler.close_file()