一: 通过lambda表达式来指定排序字段
salaries = [{'Alice': 100000, 'Bob': 24000},
{'Alice': 121000, 'Bob': 48000},
{'Alice': 12000, 'Bob': 66000}]
Use the sorted() function with key argument to create a new dic.
sorted_salaries = sorted(salaries, key=lambda d: d['Alice'])
print(sorted_salaries)
二:使用集合遍历器(Itemgetter)来指定排序字段
from operator import itemgetter
salaries = [{'Alice': 100000, 'Bob': 24000},
{'Alice': 121000, 'Bob': 48000},
{'Alice': 12000, 'Bob': 66000}]
sorted_salaries = sorted(salaries, key=itemgetter('Alice'))
print(sorted_salaries)
三：指定多个排序字段
db = [{'username': 'Alice', 'joined': 2020, 'age': 23},
{'username': 'Bob', 'joined': 2018, 'age': 19},
{'username': 'Alice', 'joined': 2020, 'age': 31}]
db_sorted = sorted(db, key=lambda row: (row['username'],
row['joined'],
row['age']))
print(db_sorted)
四：指定升序or降序
db = [{'username': 'Alice', 'joined': '2019-03-02', 'age': 23},
{'username': 'Bob', 'joined': '2020-08-08', 'age': 19},
{'username': 'Alice', 'joined': '2019-03-04', 'age': 31}]
db_sorted = sorted(db, key=lambda row: row['joined'], reverse=True)
print(db_sorted)
或者
db_sorted = sorted(db, key=lambda row: row['joined'])[::-1]