遍历 XML 文件的所有元素答案

【问题标题】：Iterate through all elements of XML file遍历 XML 文件的所有元素
【发布时间】：2015-10-29 22:40:25
【问题描述】：

我有一个这样的 XML 文件：

<CustomerOrders>
  <Customers>
    <CustomerID>ALFKI</CustomerID>
    <Orders>
      <OrderID>10643</OrderID>
      <CustomerID>ALFKI</CustomerID>
      <OrderDate>1997-08-25</OrderDate>
    </Orders>
    <Orders>
      <OrderID>10692</OrderID>
      <CustomerID>ALFKI</CustomerID>
      <OrderDate>1997-10-03</OrderDate>
    </Orders>
    <CompanyName>Alfreds Futterkiste</CompanyName>
  </Customers>
  <Customers>
    <CustomerID>ANATR</CustomerID>
    <Orders>
      <OrderID>10308</OrderID>
  <CustomerID>ANATR</CustomerID>
  <OrderDate>1996-09-18</OrderDate>
    </Orders>
    <CompanyName>Ana Trujillo Emparedados y helados</CompanyName>
  </Customers>
</CustomerOrders>

我想提取每个元素以转换为小写。我知道我可以递归地遍历所有节点和子节点，但我正在努力输出实际元素。

现在在我的代码中，我只是打印所有标签及其属性，也可以手动打印元素

import xml.etree.ElementTree as ET
tree = ET.parse('customer.xml')
root = tree.getroot()
for descendant in root.findall(".//*"):
    print descendant.tag, descendant.attrib
print root[0][1][0].text #prints 10643

我想要的是能够打印出文件的每个元素，并将它们全部转换为小写。

预期输出：

CustomerID = alfki
OrderID = 10643
CustomerID = alfki
OrderDate = 1997-08025
OrderID = 10692         
CustomerID = alfki
OrderDate = 1997-10-03
CompanyName = alfreds futterkiste

等等

【问题讨论】：

欢迎来到 StackOverflow。请阅读并遵循帮助文档中的发布指南。 MCVE 适用于此。 “我在挣扎”并没有描述问题；请编辑您的帖子以包含实际输出和您的预期。
试一试并反馈。

标签： python xml

【解决方案1】：

我的尝试如下-

import lxml.etree as et


s="""

<CustomerOrders>
  <Customers>
    <CustomerID>ALFKI</CustomerID>
    <Orders>
      <OrderID>10643</OrderID>
      <CustomerID>ALFKI</CustomerID>
      <OrderDate>1997-08-25</OrderDate>
    </Orders>
    <Orders>
      <OrderID>10692</OrderID>
      <CustomerID>ALFKI</CustomerID>
      <OrderDate>1997-10-03</OrderDate>
    </Orders>
    <CompanyName>Alfreds Futterkiste</CompanyName>
  </Customers>
  <Customers>
    <CustomerID>ANATR</CustomerID>
    <Orders>
      <OrderID>10308</OrderID>
  <CustomerID>ANATR</CustomerID>
  <OrderDate>1996-09-18</OrderDate>
    </Orders>
    <CompanyName>Ana Trujillo Emparedados y helados</CompanyName>
  </Customers>
</CustomerOrders>

"""


tree = et.fromstring(s)

for txt in tree.xpath('//text()/parent::*[1]'):
   txt.text = "%s"%txt.text.lower()

print et.tostring(tree, pretty_print=True)

打印出来-

<CustomerOrders>
  <Customers>
    <CustomerID>alfki</CustomerID>
    <Orders>
      <OrderID>10643</OrderID>
      <CustomerID>alfki</CustomerID>
      <OrderDate>1997-08-25</OrderDate>
    </Orders>
    <Orders>
      <OrderID>10692</OrderID>
      <CustomerID>alfki</CustomerID>
      <OrderDate>1997-10-03</OrderDate>
    </Orders>
    <CompanyName>alfreds futterkiste</CompanyName>
  </Customers>
  <Customers>
    <CustomerID>anatr</CustomerID>
    <Orders>
      <OrderID>10308</OrderID>
  <CustomerID>anatr</CustomerID>
  <OrderDate>1996-09-18</OrderDate>
    </Orders>
    <CompanyName>ana trujillo emparedados y helados</CompanyName>
  </Customers>
</CustomerOrders>

【讨论】：

【解决方案2】：

考虑使用XSLT 和translate() 函数。作为信息，XSLT 是一种特殊用途的编程语言，用于转换、样式化、重新格式化和重新构造 XML 文档。您可以避免 Python 中所有节点和文本的递归循环。

XSLT 脚本（另存为 .xsl 或 .xslt 以包含在 Python 中）

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*"/>

<xsl:variable name="lowercase" select="'abcdefghijklmnopqrstuvwxyz'" />
<xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />

 <!-- Identity Transform -->
 <xsl:template match="@*|node()">
   <xsl:copy>
     <xsl:apply-templates select="node()"/>
   </xsl:copy>
 </xsl:template>

 <xsl:template match="text()">       
     <xsl:value-of select="translate(., $uppercase, $lowercase)"/>       
 </xsl:template>      
</xsl:stylesheet>

Python脚本

import lxml.etree as ET

dom = ET.parse('customer.xml'))
xslt = ET.parse('XSLTscript.xsl'))
transform = ET.XSLT(xslt)
newdom = transform(dom)

tree_out = ET.tostring(newdom, encoding='UTF-8', pretty_print=True, xml_declaration=True)
print(tree_out)

xmlfile = open(os.path.join(cd, 'Output.xml'),'wb')
xmlfile.write(tree_out)
xmlfile.close()

输出

<?xml version='1.0' encoding='UTF-8'?>
<CustomerOrders>
  <Customers>
    <CustomerID>alfki</CustomerID>
    <Orders>
      <OrderID>10643</OrderID>
      <CustomerID>alfki</CustomerID>
      <OrderDate>1997-08-25</OrderDate>
    </Orders>
    <Orders>
      <OrderID>10692</OrderID>
      <CustomerID>alfki</CustomerID>
      <OrderDate>1997-10-03</OrderDate>
    </Orders>
    <CompanyName>alfreds futterkiste</CompanyName>
  </Customers>
  <Customers>
    <CustomerID>anatr</CustomerID>
    <Orders>
      <OrderID>10308</OrderID>
      <CustomerID>anatr</CustomerID>
      <OrderDate>1996-09-18</OrderDate>
    </Orders>
    <CompanyName>ana trujillo emparedados y helados</CompanyName>
  </Customers>
</CustomerOrders>

【讨论】：