Question

我尝试使用Python从混合内容文档中提取多个XML元素。用例是包含电子邮件文本但包含多个XML树的电子邮件。

以下是示例文档：

Email text email text email text email text.

email signature email signature.

<?xml version="1.0"?>
<catalog>
   <book id="bk101">
      <author>Gambardella, Matthew</author>
      <title>XML Developer's Guide</title>
      <genre>Computer</genre>
      <price>44.95</price>
      <publish_date>2000-10-01</publish_date>
      <description>An in-depth look at creating applications 
      with XML.</description>
   </book>
</catalog>

Email text email text email text email text.

email signature email signature.

<?xml version="1.0"?>
<catalog>
   <book id="bk101">
      <author>Gambardella, Matthew</author>
      <title>XML Developer's Guide</title>
      <genre>Computer</genre>
      <price>44.95</price>
      <publish_date>2000-10-01</publish_date>
      <description>An in-depth look at creating applications 
      with XML.</description>
   </book>
</catalog>

Email text email text email text email text.

email signature email signature.

<?xml version="1.0"?>
<catalog>
   <book id="bk101">
      <author>Gambardella, Matthew</author>
      <title>XML Developer's Guide</title>
      <genre>Computer</genre>
      <price>44.95</price>
      <publish_date>2000-10-01</publish_date>
      <description>An in-depth look at creating applications 
      with XML.</description>
   </book>
</catalog>

Email text email text email text email text.

email signature email signature.

我想提取XML树，以便它们可以在for循环中由XML解析器解析。我已经完善了对XML的解析，如果我采用其中一个XML树并直接解析它，它的工作就像一个魅力。

有关如何提取XML树的任何建议吗？此示例也过于简化，电子邮件文本和签名在我的每个示例中都不同，因此唯一可靠的文本是XML树的开头和结尾。

Answer 1

问题：我想提取XML树，以便XML解析器解析它们

你真的想要获得多个XML树吗？
我想建议使用多个<book子元素制作一个 XML树。

然而，这就是你想要的：

xml_tag = "<?xml"
catalog_end_tag = "</catalog>"

xml_tree = []
_xml = False
with open('test/Mixed_email_xml') as fh:
    while True:
        line = fh.readline()
        if not line: break

        if line.find(xml_tag) >=0:
            _xml = True

        if _xml:
            xml_tree.append(line)

        if line.find(catalog_end_tag) >=0:
            _xml = False

for line in xml_tree:
    print('{}'.format(line[:-1]))

使用Python测试：3.4.2

Answer 2

最简单的方法：

import re
from lxml import etree

with open('email.txt') as f:
    catalogs = ''.join(re.findall('<catalog.*?</catalog>', f.read(), re.S))
    root = etree.fromstring('<?xml version="1.0"?><root>{}</root>'.format(catalogs))

然后您可以使用root.iter('book')迭代所有book个节点。

Answer 3

在另一位非常聪明的开发人员的帮助下，这段代码解决了我的问题。

tr1 = "<?xml"
str2 = "</catalog>"
i = 0
ii = 0
tracker = []
final_ls = []

for c in data:
    for char in str1:
        if data[i + ii] == char:
            if ii == len(str1) - 1:
                tracker.append(i)
            ii += 1
    i += 1
    ii = 0

for xml in tracker:
    ii = 0
    i = xml
    for c in data[i:]:
        if ii == len(str2):
            break
        ii = 0
        for char in str2:
            if data[i + ii] == char:
                if ii == len(str2) - 1:
                    final_ls.append(data[xml:i + ii])
                    ii += 1
                else:
                    ii += 1
        i += 1

for ls in final_ls:
    print(ls)

Answer 4

我的第一个想法是使用str方法来分割所有文本，如

t = txt.split(r'<?xml version="1.0"?>')

results = [item.split("</catalog>")[0] + "</catalog>" for item in t if item.startswith("\n<catalog>")]
for i in results:
    print(i)

就像代码一样，由明显的分隔符分开。

从混合内容文档中提取多个xml树

4 个答案: