使用lxml模块分析xml文件时出现问题

Question

我试图迭代“变体”的所有“值”标记，代码不会跳转到下一个“值”键，因为xml具有另一个“值”键“第一个值KEY”

<variant> 
    <name>PROGRAMS</name> 
    <value> <!-- Lets call it FIRST VALUE KEY --> 
    <value>PROG1</value> 
    <statistics> 
     <statistic name="Stats"> 
      <value>5</value> 
     </statistic> 
    </statistics> 
    </value> 
    <value> <!-- SECOND VALUE KEY --> 
    <value>PROG2</value> 
    ... 
    </value> 
</variant> 
<variant> 
    <name>OTHER</name> 
    ... 
</variant> 

这里是我的Python代码

for keys in root.iter('variant'): 
    for variant in keys: 
     if variant.text == 'PROGRAMS': 
      for value_tag in keys.iter('value'): 
       ParamValue = value_tag.find('value').text 
        if ParamValue == 'PROG2': 
         print "GOT IT!" 
        else: continue # <- this jumps to the "<value>PROG1</value>" tag 
            # but it should jump to the "SECOND VALUE KEY" 

在哪里的问题？

Answer 1

import lxml.etree as ET 
root = ET.parse('data').getroot() 

for value in root.xpath(
    '''//variant 
      [name 
      [text()="PROGRAMS"]] 
     /value 
      [value 
      [text()="PROG2"]]'''): 
    print('GOT IT') 

产生

GOT IT 

---

我认为这是比较容易use XPath向下挖掘到你想要的元素。 中的XPath意味着

//       # look for all elements 
variant     # that are variants 
    [name     # that have a <name> element 
    [text()="PROGRAMS"]] # with text equal to "PROGRAMS" 
/value     # select the <value> (child of variant) 
    [value     # that has a child <value> element 
    [text()="PROG2"]]  # with text equal to "PROG2" 

---

遍历<statistics>儿童<value>元素：

for statistics in root.xpath(
    '''//variant 
      [name 
      [text()="PROGRAMS"]] 
     /value 
      [value 
      [text()="PROG2"]] 
      /statistics'''): 

在XPath，括号[..]松散翻译成 “这样”。请注意，如果没有括号，上面的XPath将是//variant/value/statistics。它看起来有点像文件路径。和文件路径一样，它显示了元素的谱系。一个/意味着“直接子女”，而//意味着“子孙后代”（例如儿童，孙子或孙子女等）。