在中使用Python字典进行文本替换re.sub公司

Question

我有以下格式的输入文件：

<ftnt>
<p><su>1</su> aaaaaaaaaaa </p>
</ftnt>
...........
...........
...........
... the <su>1</su> is availabe in the .........

我需要通过替换值并删除ftnt标记中的全部数据，将其转换为以下格式：

^{pr2}$

请找出我写的代码。最初，我将键和值保存在字典中，并尝试使用分组替换基于键的值。在

import re
dict = {}
in_file = open("in.txt", "r")
outfile = open("out.txt", "w")
File1 = in_file.read()

infile1 = File1.replace("\n", " ")
for mo in re.finditer(r'<p><su>(\d+)</su>(.*?)</p>',infile1):

     dict[mo.group(1)] = mo.group(2)

subval = re.sub(r'<p><su>(\d+)</su>(.*?)</p>','',infile1)
subval = re.sub('<su>(\d+)</su>',dict[\\1], subval)

outfile.write(subval)

我试图在re.sub中使用字典，但是我得到了一个KeyError。我不知道为什么会这样，你能告诉我怎么用吗。我很感激你的帮助。在

Answer 1

首先，不要命名字典dict，否则会破坏dict函数。其次，\\1不能在字符串之外工作，因此出现语法错误。我认为最好的办法是利用str.format

import re

# store the substitutions
subs = {}

# read the data
in_file = open("in.txt", "r")
contents = in_file.read().replace("\n", " ")
in_file.close()

# save some regexes for later
ftnt_tag = re.compile(r'<ftnt>.*</ftnt>')
var_tag = re.compile(r'<p><su>(\d+)</su>(.*?)</p>')

# pull the ftnt tag out
ftnt = ftnt_tag.findall(contents)[0]
contents = ftnt_tag.sub('', contents)

# pull the su
for match in var_tag.finditer(ftnt):
    # added s so they aren't numbers, useful for format
    subs["s" + match.group(1)] = match.group(2)

# replace <su>1</su> with {s1}
contents = re.sub(r"<su>(\d+)</su>", r"{s\1}", contents)

# now that the <su> are the keys, we can just use str.format
out_file = open("out.txt", "w")
out_file.write( contents.format(**subs) )
out_file.close()