Python base (8) facing the object in the base (1)

1. The first object-oriented

class Cat:

    def eat(self):
        print("小猫爱吃鱼")

    def drink(self):
        print("小猫要喝水")


# 创建猫对象
tom = Cat()

tom.eat()
tom.drink()

print(tom)

addr = id(tom)
print("%x" % addr)

2. Create two Cat objects

class Cat:

    def eat(self):
        print("小猫爱吃鱼")

    def drink(self):
        print("小猫要喝水")


# 创建猫对象
tom = Cat()

tom.eat()
tom.drink()

print(tom)

# 再创建一个猫对象
lazy_cat = Cat()

lazy_cat.eat()
lazy_cat.drink()

print(lazy_cat)

lazy_cat2 = lazy_cat

print(lazy_cat2)

3. Set the object properties _self

class Cat:

    def eat(self):
        # 哪一个对象调用的方法，self就是哪一个对象的引用
        print("%s 爱吃鱼" % self.name)

    def drink(self):
        print("%s 要喝水" % self.name)


# 创建猫对象
tom = Cat()

# 可以使用　.属性名　利用赋值语句就可以了
tom.name = "Tom"

tom.eat()
tom.drink()

print(tom)

# 再创建一个猫对象
lazy_cat = Cat()

lazy_cat.name = "大懒猫"

lazy_cat.eat()
lazy_cat.drink()

print(lazy_cat)

4. Set the properties in question outside

class Cat:

    def eat(self):
        # 哪一个对象调用的方法，self就是哪一个对象的引用
        print("%s 爱吃鱼" % self.name)

    def drink(self):
        print("%s 要喝水" % self.name)


# 创建猫对象
tom = Cat()

# 可以使用　.属性名　利用赋值语句就可以了
# tom.name = "Tom"

tom.eat()
tom.drink()
tom.name = "Tom"

The initialization method

class Cat:

    def __init__(self):

        print("这是一个初始化方法")

        # self.属性名 = 属性的初始值
        self.name = "Tom"

    def eat(self):
        print("%s 爱吃鱼" % self.name)

# 使用类名()创建对象的时候，会自动调用初始化方法 __init__
tom = Cat()

print(tom.name)

6. The use of the initial value of the attribute parameter

class Cat:

    def __init__(self, new_name):

        print("这是一个初始化方法")

        # self.属性名 = 属性的初始值
        # self.name = "Tom"
        self.name = new_name

    def eat(self):
        print("%s 爱吃鱼" % self.name)

# 使用类名()创建对象的时候，会自动调用初始化方法 __init__
tom = Cat("Tom")

print(tom.name)

lazy_cat = Cat("大懒猫")
lazy_cat.eat()

7.del method

class Cat:

    def __init__(self, new_name):

        self.name = new_name

        print("%s 来了" % self.name)

    def __del__(self):

        print("%s 我去了" % self.name)

# tom 是一个全局变量
tom = Cat("Tom")
print(tom.name)

# del 关键字可以删除一个对象
del tom

print("-" * 50)

8.str method

class Cat:

    def __init__(self, new_name):

        self.name = new_name

        print("%s 来了" % self.name)

    def __del__(self):

        print("%s 我去了" % self.name)

    def __str__(self):

        # 必须返回一个字符串
        return "我是小猫[%s]" % self.name

# tom 是一个全局变量
tom = Cat("Tom")
print(tom)

9. Xiaoming love running

class Person:

    def __init__(self, name, weight):

        # self.属性 = 形参
        self.name = name
        self.weight = weight

    def __str__(self):

        return "我的名字叫 %s 体重是 %.2f 公斤" % (self.name, self.weight)

    def run(self):
        print("%s 爱跑步，跑步锻炼身体" % self.name)

        self.weight -= 0.5

    def eat(self):
        print("%s 是吃货，吃完这顿再减肥" % self.name)

        self.weight += 1

xiaoming = Person("小明", 75.0)

xiaoming.run()
xiaoming.eat()

print(xiaoming)

10. Small Caritas running extension

class Person:

    def __init__(self, name, weight):

        # self.属性 = 形参
        self.name = name
        self.weight = weight

    def __str__(self):

        return "我的名字叫 %s 体重是 %.2f 公斤" % (self.name, self.weight)

    def run(self):
        print("%s 爱跑步，跑步锻炼身体" % self.name)

        self.weight -= 0.5

    def eat(self):
        print("%s 是吃货，吃完这顿再减肥" % self.name)

        self.weight += 1

xiaoming = Person("小明", 75.0)

xiaoming.run()
xiaoming.eat()

print(xiaoming)

# 小美爱跑步
xiaomei = Person("小美", 45)

xiaomei.eat()
xiaomei.run()

print(xiaomei)
print(xiaoming)