如果 findall 找到搜索模式，则在文件中插入新行

Question

我想在 findall 找到搜索模式后向文件添加新行。我使用的代码只将输入文件的内容写入输出文件。它不会向输出文件添加新行。我该如何修复我的代码？

import re
text = """
Hi! How are you?
Can you hear me?
"""
with open("input.txt", "r") as infile:
    readcontent = infile.readlines()

with open("output.txt", "w") as out_file:
    for line in readcontent:
    x1 = re.findall(text, line)
    if line == x1:
        line = line + text
    out_file.write(line)

Input.txt:

ricochet robots
settlers of catan
acquire
Hi! How are you?
Can you hear me?
this is very valuable
finish

想要output.txt：

ricochet robots
settlers of catan
acquire
Hi! How are you?
Can you hear me?

Added new line

this is very valuable
finish

Answer 1

尝试遍历每一行并检查您的文本是否存在。

例如：

res = []
with open(filename, "r") as infile:
    for line in infile:
        if line.strip() == "Hi! How are you?":
            res.append(line.strip())
            lineVal = (next(infile)).strip() 
            if lineVal == "Can you hear me?":
                res.append(lineVal)
                res.append("\n Added new line \n")
        else:
            res.append(line.strip())



with open(filename1, "w") as out_file:
    for line in res:
        out_file.write(line+"\n")

输出：

ricochet robots
settlers of catan
acquire
Hi! How are you?
Can you hear me?

 Added new line 

this is very valuable
finish

Answer 2

这是你想要的吗：

text = "Can you hear me?"
with open("input.txt", "r") as infile:
    readcontent = infile.readlines()

with open("output.txt", "w") as out_file:
    for idx,line in enumerate(readcontent):
       if line.rstrip() == text:
           line+='\nAdded new line\n\n'
       out_file.write(line)

output.txt 看起来像：

ricochet robots
settlers of catan
acquire
Hi! How are you?
Can you hear me?

Added new line

this is very valuable
finish

Answer 3

这里不用regex。检查当前行，如果是要检查的行，则添加一个换行符。

with open("output.txt", "w") as out_file:
    for line in readcontent:
        out_file.write(line)
        if line.strip() == 'Can you hear me?':
            out_file.write('\n')

如果您本身需要 regex，请执行以下操作（尽管我绝不会推荐）：

with open("output.txt", "w") as out_file:
    for line in readcontent:
        out_file.write(line)
        if re.match('Can you hear me?', line.strip()):
            out_file.write('\n')

如果 findall 找到搜索模式，则在文件中插入新行

insert a new line to a file if findall finds a search pattern

python

regex

findall

python-2.7

python-3.x