python练习之查找一个文件中的字符串是否在另一个文件中存在

不得不说正则是个好东西。

没错这次又用到正则表达式。
直接上代码：

# -*- coding: UTF-8 -*-

import re                                                 #使用正则库

# 打开文件
fo = open("hello.txt", "r");
co = open("world.txt", "r");

colines = co.readlines();                       #读取所有world文件中的行

for line in fo.readlines():                        #依次读取每行  
    line = line.strip();                              #去掉每行头尾空白  
    matchObj = re.search( line, "%s" %  colines, re.M | re.I);
   #正则匹配开始，使用search可以将全部符合条件的字符集都找出来
   if matchObj:
        print line;

# 关闭文件
fo.close();
co.close();

hello.txt里面内容：

hello
world
good
nod

world.txt里面内容：

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaworldaaaaaaaaaaaaaaaaaaaaaa
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbworldskkkkkkkkkkkkkkkkkkkkkkkkkkk
ssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss
dddddddddddddddddddddddddddddddddddd
dfgggggggggggggggggggggggggggggggggggggggg
ggggggggggggggggggggggggggggggggggggggggggggggg
eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
worldnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn
wwwwwwwwwwwwwwwwwwwwwworldddddddddddddddddddddddddddddddddddd
dnmnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnhellolllllllllllllllllllllll
ddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddqqqqqqqqqqqqqqqq
qqqqqqqqqqqneeeeeeeeeehello,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
sdfsdfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
hello
ddddddddddddddddddddddddddddddddddddddddd

运行结果：

image.png