打开文件
#f = open("yesterday",'r+',encoding="utf-8") #读写 #f = open("yesterday",'w+',encoding="utf-8") #写读 #f = open("yesterday",'a+',encoding="utf-8") #追加写读 #f = open("yesterday",'wb') #写读 二进制文件
打印一行内容
f = open("yesterday",'r+',encoding="utf-8") #读写 print(f.readline())#打印一行内容
上面方法一次只能打印一行的内容,如果要打印多行内容,该怎么办呢
可以打印多行内容
f = open("yesterday",'r+',encoding="utf-8") #读写 print(f.readline())#打印一行内容 print(f.readline()) print(f.readline()) print(f.readline())
这个方法可以打印4行内容。
我要打印1000行的话,上面的方法就不现实了
使用for可以打印多行文件
f = open("yesterday",'r',encoding="utf-8")#文件句柄 count = 0 for line in f: if count == 4: print('------我是分割线------') count += 1 continue print(line) count += 1
修改文件内容
f = open("yesterday",'r',encoding='utf-8') f_new = open('new_yesterday','w',encoding='utf-8') for line in f: if "夜夜笙歌" in line: line = line.replace("夜夜笙歌","拉啦大便") f_new.write(line) f.close() f_new.close()
使用with也可以打开文件,并且在文件操作之后不需要再单独关闭文件
with open('new_yesterday','r',encoding='utf-8') as f,\ open('yesterday','r',encoding='utf-8') as f2: for line in f: print(line)