python之attrgetter函数对对象排序

 # 使用attrgetter函数对对象排序
 # attrgetter处理对象，itemgetter处理序列

 from operator import attrgetter

 class user():
     def __init__(self, name, age):
         self.name = name
         self.age = age

     def __repr__(self):
         '''定义该对象需要输出时的字符串格式'''
         return self.name + ":" + str(self.age)

 users = [
     user("Mike", 28),
     user("Lily", 25),
     user("Tom", 27),
     user("Ben", 23)
 ]

 print('排序前：')
 for user in users:
     print(user)

 print('-' * 20)
 print('排序后：')

 for u in sorted(users, key=attrgetter("name")):
     '''根据对象名称排序-key(u)'''
     print(u)

 for u in sorted(users, key=attrgetter("name", "age")):
     '''多键值排序'''
     print(u)

运行结果：

 排序前：
 Mike:28
 Lily:25
 Tom:27
 Ben:23
 --------------------
 排序后：
 Ben:23
 Lily:25
 Mike:28
 Tom:27