Python 文件的练习

1. 把一个数字的list从小到大排序，然后写入文件，然后从文件中读取出来文件内容，然后反序，在追加到文件的下一行中

#从小到大排序
import codecs
list1 = [1,3,8,5,2]
list1.sort()

#写入文件 换行写在文件中

import codecs

list1 = [1,3,8,5,2]
list1.sort()
f = codecs.open('training01.txt','wb')
for i in list1:
    f.write(str(i))
    f.write('\n')
f.close()

#反序

list1 = [1,3,8,5,2]
list1.sort()
list1.reverse()

#追加 反序

import codecs

list1 = [1,3,8,5,2]
list1.sort()
f = codecs.open('training01.txt','wb')
for i in list1:
    f.write(str(i))
    f.write('\n')
f.close()
list1.reverse()
b = list1
#print b
w = codecs.open('training01.txt','ab')
for i in b:
    w.write('\n')
    w.write(str(i))
w.close()

#整理一个文件

import codecs

list1 = [1,3,8,5,2]
list1.sort()
f = codecs.open('training01.txt','wb')                  # 把列表写入文件
for i in list1:
    f.write(str(i))
    f.write('\n')
f.close()                    
list1.reverse()
b = list1
#print b
w = codecs.open('training01.txt','ab')                  #把列表反转追加到文件中
for i in b:
    w.write('\n')
    w.write(str(i))
w.close()

str1 = 'abcd'                                           #追加字符串
w = codecs.open('training01.txt','ab')
for i in str1:
    w.write(str(i))
w.close()

tub = (1,2,'a','b','c')                                 #追加元组
with codecs.open('training01.txt','ab') as w:
    w.write('\n')
    for i in tub:
        w.write(str(i))

dic1 = {1:2,'a':123}                                    #追加字典
with codecs.open('training01.txt','ab') as w:
    w.write('\n')
    for d in dic1.iteritems():
        w.write('\n')
        for i in d:
            w.write(str(i))