将文本每行读入一个数组中啊 然后直接用python 中数组 insert() 插入
file = open("C:/a.txt", "r")
li = []
#line_counter = 0
while 1:
line = file.readline()
if line:
li.append(line)
else:
break
file.close()
lines = len(li)
‘’‘
下面从倒数第三行开始插入想要插入的
字符串,每行插入的字符用\n分开。如果要写的东西多,可以从外部文件读入数据
’‘’
li.insert(lines-3,"1st row you want to write \n 2nd row you want to write \n")
file=open("C:/a.txt", "w")
for line in li:
file.write(line)
file.close()本回答被提问者采纳