每天CookBook之Python-014

• attrgetter的使用

attrgetter函数用于获取对象的指定属性值

from operator import attrgetter


class User(object):
    """docstring for User"""

    def __init__(self, user_id):
        self.user_id = user_id

    def __repr__(self):
        return 'User(%s)' % self.user_id


users = [User(23), User(3), User(99)]
print(users)

print(sorted(users, key=lambda u: u.user_id))

print(sorted(users, key=attrgetter('user_id')))

print(min(users, key=attrgetter('user_id')))
print(max(users, key=attrgetter('user_id')))

[User(23), User(3), User(99)]
[User(3), User(23), User(99)]
[User(3), User(23), User(99)]
User(3)
User(99)