在平面xml文件中创建结构

我不知道python,但是假设您有一个XML解析器,它允许您对XML文档中的节点进行分层访问,那么您想要的语义应该是如下所示的(警告,我倾向于使用PHP)。基本上,存储任何非“car”标记,然后当您遇到一个新的“car”标记时,将其视为一个定界字段,并创建组装的XML节点:

// Create an input and output handle
input_handle = parse_xml_document();
output_handle = new_xml_document();

// Assuming the <car>, <color> etc. nodes are
// the children of some, get them as an array
list_of_nodes = input_handle.get_list_child_nodes();

// These are empty variables for storing our data as we parse it
var car, color, speed = NULL

foreach(list_of_nodes as node)
{
  if(node.tag_name() == "speed")
  {
    speed = node.value();
    // etc for each type of non-delimiting field          
  }

  if(node.tag_name() == "car")
  {
    // If there's already a car specified, take its data,
    // insert it into the output xml structure and th
    if(car != NULL)
    {
      // Add a new child node to the output document
      node = output_handle.append_child_node("car");
      // Set the attribute on this new output node
      node.set_attribute("name", node.value());
      // Add the stored child attributes
      node.add_child("color", color);
      node.add_child("speed", speed);
    }

    // Replace the value of car afterwards. This allows the
    // first iteration to happen when there is no stored value
    // for "car".
    car = node.value();

  }
}

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

  <!-- copy the root element and handle its <car> children -->
  <xsl:template match="/root">
    <xsl:copy>
      <xsl:apply-templates select="car" />
    <xsl:copy>
  </xsl:template>

  <!-- car elements become a container for their properties -->
  <xsl:template match="car">
    <car name="{normalize-space()}">
      <!-- ** see 1) -->
      <xsl:copy-of select="following-sibling::color[1]" />
      <xsl:copy-of select="following-sibling::speed[1]" />
    </car>
  </xsl:template>
</xsl:stylesheet>

1) 为此,您的XML必须有一个 <color> 和一个 <speed> 每 <car> . 如果不能保证,或者属性的数量和种类通常是可变的,请用copy语句的通用形式替换这两行:

<!-- any following-sibling element that "belongs" to the same <car> -->
<xsl:copy-of select="following-sibling::*[
  generate-id(preceding-sibling::car[1]) = generate-id(current())
]" />

<root> ),这就是结果

<root>
  <car name="Ferrari">
    <color>red</color>
    <speed>300</speed>
  </car>
  <car name="Porsche">
    <color>black</color>
    <speed>310</speed>
  </car>
</root>

在Python中将XSLT应用于XML的示例代码应该很容易找到,所以我在这里省略了它。它几乎不超过4到5行Python代码。

如果 您的实际数据和您的示例一样简单,并且没有错误,您可以使用正则表达式替换一次性完成:

import re

guff = """
<car>Ferrari</car>
<color>red</color>
<speed>300</speed>
<car>Porsche</car>
<color>black</color>
<speed>310</speed>
"""

pattern = r"""
<car>([^<]+)</car>\s*
<color>([^<]+)</color>\s*
<speed>([^<]+)</speed>\s*
"""

repl = r"""<car name="\1">
    <color>\2</color>
    <speed>\3</speed>
</car>
"""

regex = re.compile(pattern, re.VERBOSE)
output = regex.sub(repl, guff)
print output

假设根中的第一个元素是 car 汽车 元素“属于”最后一个元素 汽车 :

import xml.etree.cElementTree as etree

root = etree.XML('''<root>
<car>Ferrari</car>
<color>red</color>
<speed>300</speed>
<car>Porsche</car>
<color>black</color>
<speed>310</speed>
</root>''')

new_root = etree.Element('root')

for elem in root:
    if elem.tag == 'car':
        car = etree.SubElement(new_root, 'car', name=elem.text)
    else:
        car.append(elem)

new_root

<root><car name="Ferrari"><color>red</color>
<speed>300</speed>
</car><car name="Porsche"><color>black</color>
<speed>310</speed>
</car></root>

(我认为漂亮的空白并不重要)