Python字典排序OrderedDict

在Python2.7.x版本中, collections类增加了OrderedDict, 用法如下： 

 

pywugw@pywugw-laptop:~$/usr/local/bin/python2.7
Python 2.7b1(r27b1:79927, Apr 26 2010, 11:44:19)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits"or "license" for more information.
>>>from collections import OrderedDict
>>> d= {'banana': 3,'apple':4,'pear': 1,'orange': 2}

#按key排序
>>>OrderedDict(sorted(d.items(), key=lambda t: t[0]))
OrderedDict([('apple',4),('banana', 3),('orange', 2),('pear', 1)])

#按value排序
>>>OrderedDict(sorted(d.items(), key=lambda t: t[1]))
OrderedDict([('pear',1),('orange', 2),('banana', 3),('apple', 4)])

#按key的长度排序
>>>OrderedDict(sorted(d.items(), key=lambda t: len(t[0])))
OrderedDict([('pear',1),('apple', 4),('orange', 2),('banana', 3)])