python入门之两种方法修改文件内容

1.占硬盘修改

import os

file_name="兼职.txt"

new_file_name="%s.new".% file_name

old_str="hong" #需要替换的量

new_str="洪"#需要替换成的量

old_f=open(file_name,"read")

new_f=open(new_file_name,"w")

for line in file_name:

      if old_str in line:

            line=line.replace(old_str,new_str)

      new_f.write(line)

old_f.close()

new_f.close()

ox.rename(new_file_name,file_name)  #新的文件夹把旧的文件夹覆盖掉

2.占内存修改

old_str = "hong"

new_str = "洪"

file_name = "兼职.txt"

f=open(file_name,"r+")

data=f.read()

a = data.replace(old_str,new_str)

f.truncate(0)

f.write(a)

f.close()