python 如何根据关键字提取 txt 文件的一部分？

Question

给定一个包含 ~5000 HTML 个文档的非常大的文本文件。我正在尝试 "search" 特定 DOCNO 的文本文件并打印文件的所有行，直到遇到下一个 </DOC> 标记。

文本文件大致如下所示：

<DOC>
<DOCNO>abc4567890</DOCNO>
contents 
more contents
<BODY> 
even more contents 
</BODY>
</DOC> 
... repeated roughly 5000 times for different DOC NO's

我正在寻找以下输出：

contents 
more contents
<BODY> 
even more contents 
</BODY>
</DOC>

这是我一直在努力实现的：

doc_string = "abc4567890"

with open('myfile.txt', encoding = "utf8") as f:
    for item in f.readlines():
        if "</DOCNO>" in item:
                ID = (item [ item.find("<DOCNO>")+len("<DOCNO>") : ])
                if (ID[0:9] == doc_string):
                    print (item)
                    if "</DOC>" in item:
                       break

但是，作为输出，我得到：

<DOCNO>abc4567890</DOCNO>

Answer 1

这样的怎么样？

# initialize variables:
lines = []
read_lines = False

with open('file.txt', 'r') as file:

    # iterate over each line:    
    for line in file.readlines():

        # append line to lines list:
        if read_lines: lines.append(line)

        # set read_lines to True:
        if '<DOCNO>abc4567890</DOCNO>' in line: read_lines = True

        # set read_lines to Flase:
        if '</DOC>' in line: read_lines = False


# print each line:
for line in lines:
    print(line, end='')

根据您的输入，它将输出：

contents 
more contents
<BODY> 
even more contents 
</BODY>
</DOC>

python 如何根据关键字提取 txt 文件的一部分？

How to extract a portion of a txt file based on a keyword, in python?

python

tags

extract