1 文件内容互相复制
a = open(r'C:\Users\kk\Desktop\a.txt','r')
b = open(r'C:\Users\kk\Desktop\b.txt','w+')
for h in a.readlines():
b.writelines(h)
a.close()
b.close()
或者：
import shutil
shutil.copyfile(r'C:\Users\kk\Desktop\a.txt', r'C:\Users\kk\Desktop\d.txt')
2 将a文件复制到b文件 并且每行长度为8个字符
a = open(r'C:\Users\kk\Desktop\a.txt','r+')
b = open(r'C:\Users\kk\Desktop\b.txt','w+')
i=8
for c in a.readlines():
for h in range(0,len(c),i):
aa = c[h:h+i]+'\n'
print aa
b.write(aa)
3 替换文本中的某行 。将文本所有行变成列表然后切片
file = open(r'C:\Users\kk\Desktop\a.txt','r+')
b = file.readlines()
b[1] = 'hello'
file = open(r'C:\Users\kk\Desktop\a.txt','w+')
file.writelines(b)
file.close()
4 替换文本中某个字符
import re
file = open(r'C:\Users\kk\Desktop\a.txt','r+')
open(r'C:\Users\kk\Desktop\c.txt', 'w').write(re.sub('hello', 'Love python', file.read()))
5 查找某个字符在多少行
file = open(r'C:\Users\kk\Desktop\a.txt','r+')
for h ,num in enumerate(file.readlines()):
if num.find('kexl') >= 0:
print h,num
file.close()
