P132 魔术方法

• 参考文档

1. 魔术方法的基本介绍

2. 常见的魔术方法

2.1 str

# 请输出Monster[name，job，sal]对象的属性信息
#可以根据需要重写__str__
class Monster:def __init__(self, name, age, gender):self.name = nameself.age = ageself.gender = gender"""说明:1. 在默认情况下,调用的是父类Object的__str__2. 父类Object的__str__返回的就是类型+地址3. 可以根据需要重写__str__"""def __str__(self):return f"{self.name}, {self.age}, {self.gender}"m = Monster("青牛怪", 500, '男')print(m) #默认输出类型+对象的地址

2.2 eq

• 基本介绍
  
• 应用实例
  

# 代码演示
# 原代码class Person:name = Noneage = Nonegender = Nonedef __init__(self, name, age, gender):self.name = nameself.age = age# 没有重写__eq__ 前,== 比较的是内存地址
p1 = Person("smith",20,"男")
p2 = Person("smith",20,"男")print(f"p1==p2: {p1 == p2}")

# 代码演示
# 代码改进# 代码演示class Person:name = Noneage = Nonegender = Nonedef __init__(self, name, age, gender):self.name = nameself.age = ageself.gender =gender# 判断两个Person对象的内容是否相等，# 如果两个Person对象的各个属性值都一样，则返回true，反之falsedef __eq__(self, other):# 判街other是不是Personif isinstance(other,Person):return self.name == other.name and \self.age == other.age and \self.gender == other.genderreturn Falseclass Dog:name = Noneage = Nonegender = Nonedef __init__(self, name, age, gender):self.name = nameself.age = ageself.gender = gender# 没有重写__eq__ 前,== 比较的是内存地址
p1 = Person("smith", 20, "男")
p2 = Person("smith", 20, "男")dog = Dog("smith", 20, "男")print(f"p1==p2: {p1 == p2}") # T
print(f"p1==p2: {dog == p2}")  # T

2.3 其它的几个魔术方法

# 代码演示class Person:name = Noneage = Nonegender = Nonedef __init__(self, name, age, gender):self.name = nameself.age = ageself.gender = gender# 判断两个Person对象的内容是否相等，# 如果两个Person对象的各个属性值都一样，则返回true，反之falsedef __eq__(self, other):# 判街other是不是Personif isinstance(other, Person):return self.name == other.name and \self.age == other.age and \self.gender == other.genderreturn False# 重写__lt__def __lt__(self, other):# 判街other是不是Personif isinstance(other, Person):return self.age < other.agereturn "类型不一致,不能比较"# 重写__le__def __le__(self, other):# 判街other是不是Personif isinstance(other, Person):return self.age <= other.agereturn "类型不一致,不一致"# 重写__ne__def __ne__(self, other):return not self.__eq__(other)class Dog:name = Noneage = Nonegender = Nonedef __init__(self, name, age, gender):self.name = nameself.age = ageself.gender = gender# 没有重写__eq__ 前,== 比较的是内存地址
p1 = Person("smith", 20, "男")
p2 = Person("smith", 20, "男")dog = Dog("smith", 20, "男")# # 重写__eq__ 前,== 比较的是内容和属性
# print(f"p1==p2: {p1 == p2}")  # T
# print(f"p1==p2: {dog == p2}")  # Tprint(f"p1 < p2 {p1 < p2}")
print(f"p1 <= p2 {p1 <= p2}")