python 练习

#!/usr/bin/env python

# -*- coding:utf-8 -*-

# @Time   : 2017/10/30 0030 11:58

# @File   : David.py

#正向排序

import codecs

l = [1,5,3,8,2,4]

l.sort()

#写入文件

with codecs.open('1.txt','wb') as fd:

    for i in l:

        fd.write(str(i))

    fd.write('\n')

#读取文件并还原成列表

l1=[]

with codecs.open('1.txt','rb') as fd:

    for i in fd.read():

        l1.append(i)

#反向排序

l1.reverse()

#删除空格

l1.remove('\n')

#追加写入列表

with codecs.open('1.txt','ab') as fd:

     for i in l1:

        fd.write(str(i))

#追加字符串

str1 = 'abc'

with codecs.open('1.txt','ab') as fd:

    fd.write('\n')

    fd.write(str1)

#追加列表

li = [1,2,3]

with codecs.open('1.txt', 'ab') as fd:

    fd.write('\n')

    for i in li:

        fd.write(str(i))

#追加元组

tu = ('one','two','three')

with codecs.open('1.txt', 'ab') as fd:

    fd.write('\n')

    for i in tu:

        fd.write(i)

#追加字典

dic = {1:'a',2:'b'}

with codecs.open('1.txt', 'ab') as fd:

    for line in dic.iteritems():

        fd.write('\n')

        for i in line:

            fd.write(str(i))