#!/usr/bin/env python # -*- coding:utf-8 -*-         #第二行声明编码 gbk #文件修改 f1=open('xxx.txt','r',encoding='utf-8') f2=open('x2.txt','w',encoding='utf-8') print(f1.readline()) for line in f1:     if 'nihao' in line:         line = line.replace('hao','hAo')     f2.write(line) f1.close() f2.close() #自动关闭文件 with open('x2.txt','r',encoding='utf-8') as f:     for i in f:         print(i) #打开多个文件 with open('xxx.txt') as f1,open('x2.txt') as f2:     pass #一行代码不超过80个字符 with open('xxx.txt') as f1,open('x2.txt') as f2 ,\         open('qq.txt','r',encoding='utf-8') as f3:     pass #显示系统默认编码 import  sys print(sys.getdefaultencoding()) #转码 a='你好'  #默认utf-8 b=a.encode("gbk")   #转换成GBK  不显示中文 print(b) c=b.decode("gbk").encode("utf-8")   #转utf8 print(c)