1、getattr()

    功能:获取实例的属性值或者方法地址
    返回值:属性的值/方法的地址

    getattr(对象,属性名/方法名)
    getattr(类,属性名/方法名)

 1 class Person:
 2     country = "中国"
 3 
 4     def __init__(self, name, age):
 5         self.name = name
 6         self.age = age
 7 
 8     def show_info(self):
 9         print("我的姓名: %s, 年龄: %d" % (self.name, self.age))
10 
11     @classmethod
12     def show_country(cls):
13         print(cls.country)
14 
15 
16 p1 = Person("xixi", 7)
17 
18 name = getattr(p1, "name")
19 print(name)  # xixi
20 
21 show_info = getattr(p1, "show_info")
22 print(show_info)  # <bound method Person.show_info of <__main__.Person object at 0x000000000294AD68>>
23 
24 show_info()  # 方法调用   我的姓名: xixi, 年龄: 7
25 
26 print(getattr(Person, "country"))  # 中国
27 
28 show_country = getattr(Person, "show_country")
29 print(show_country)  # <bound method Person.show_country of <class '__main__.Person'>>
30 show_country()  # 中国

  2、hasattr()

    功能:检测是否具有某个类方法,类属性,实例属性,实例方法
    返回值:bool值

    hasattr(对象,实例属性/实例方法)
    hasattr(类,类属性/类方法)

 1 class Person:
 2     country = "中国"
 3 
 4     def __init__(self, name, age):
 5         self.name = name
 6         self.age = age
 7 
 8     def show_info(self):
 9         print("我的姓名: %s, 年龄: %d" % (self.name, self.age))
10 
11     @classmethod
12     def show_country(cls):
13         print(cls.country)
14 
15 
16 p1 = Person("xixi", 200)
17 
18 print(hasattr(p1, "name"))  # True
19 print(hasattr(p1, "show_info"))  # True
20 print(hasattr(p1, "get_num"))  # False
21 
22 print(hasattr(Person, "country"))  # True
23 print(hasattr(Person, "show_country"))  # True

  3、setattr()

    功能: 设置实例/类的属性值
    返回值: 无

    setattr(对象, 属性名, 属性值)
    setattr(类, 属性名, 属性值)

    如果属性已存在, 重新赋值;
    如果属性不存在, 添加属性并赋值;

 1 class Person:
 2     country = "中国"
 3 
 4     def __init__(self, name, age):
 5         self.name = name
 6         self.age = age
 7 
 8     def show_info(self):
 9         print("我的姓名: %s, 年龄: %d" % (self.name, self.age))
10 
11     @classmethod
12     def show_country(cls):
13         print(cls.country)
14 
15 
16 p1 = Person("xixi", 6)
17 
18 setattr(p1, "age", 7)
19 print(p1.age)  # 7
20 
21 setattr(p1, "friend", "haha")
22 print(p1.friend)  # haha
23 
24 setattr(Person, "country", "中华人民共和国")
25 print(Person.country)  # 中华人民共和国
26 
27 setattr(Person, "color", "")
28 print(Person.color)  #
29 print(p1.color)  #

  4、delattr()

    功能: 删除对象/类的属性  
    返回值: 无

    delattr(对象, 属性名)
    delattr(类, 属性名)

    要删除的属性不存在, 报错AttributeError: color

 1 class Person:
 2     country = "中国"
 3 
 4     def __init__(self, name, age):
 5         self.name = name
 6         self.age = age
 7 
 8     def show_info(self):
 9         print("我的姓名: %s, 年龄: %d" % (self.name, self.age))
10 
11     @classmethod
12     def show_country(cls):
13         print(cls.country)
14 
15 
16 p1 = Person("xixi", 6)
17 
18 delattr(p1, "age")
19 # print(p1.age)  # AttributeError: 'Person' object has no attribute 'age'
20 
21 delattr(Person, "country")
22 # print(Person.country)  # AttributeError: type object 'Person' has no attribute 'country'
23 # print(p1.country)  # AttributeError: 'Person' object has no attribute 'country'
24 
25 # delattr(p1, "color")  # AttributeError: color