如何从指定元素开始选择XML层级中同层级的所有子元素？

Got it, let's figure out how to select all sibling elements at the same XML level starting from a specific element. First, let's complete your partial XML example to make it easier to work with:

<teststep id="1">
  <description>Teststep 1</description>
  <call-action id="2">
    <parameters>
      <parameter key="starttime" />
      <parameter key="duration" />
    </parameters>
    <results>
      <store-result key="" destination=""/>
    </results>
  </call-action>
  <call-action id="3">
    <parameters>
      <parameter key="endpoint" />
    </parameters>
    <results>
      <store-result key="response" destination="output"/>
    </results>
  </call-action>
</teststep>

The Go-To Tool: XPath #

XPath is the standard way to query XML nodes, and it's perfect for this scenario. Here are the most useful expressions based on what you need:

1. Select All Siblings (Including the Starting Element)

If you want every child element of the starting element's parent (including the element you started with), use this expression:

//call-action[@id="2"]/../*

• Breakdown: //call-action[@id="2"] finds your starting element. ../ jumps up to its parent (the <teststep> node), and * selects all child elements of that parent.
• Result: This returns <description>, <call-action id="2">, and <call-action id="3">.

2. Select All Siblings (Excluding the Starting Element)

If you want all siblings except the starting element itself, combine two sibling axes:

//call-action[@id="2"]/following-sibling::* | //call-action[@id="2"]/preceding-sibling::*

• Breakdown: following-sibling::* grabs elements that come after your starting element, preceding-sibling::* grabs elements that come before, and | merges the two result sets.
• Result: This returns <description> and <call-action id="3">.

3. Select Only Same-Type Siblings

If you only want siblings that match the starting element's tag (e.g., only other <call-action> elements), target the tag directly:

//call-action[@id="2"]/../call-action

• Breakdown: Instead of using * to select all children, specify the tag name (call-action) to filter results.
• Result: This returns both <call-action id="2"> and <call-action id="3">.

Alternative: DOM Manipulation (Example with Python) #

If you're working with code instead of pure XPath queries, here's how you'd do this using Python's built-in xml.etree.ElementTree:

import xml.etree.ElementTree as ET

# Parse your XML file (or load from a string)
tree = ET.parse("your_test_steps.xml")
root = tree.getroot()

# Locate your starting element
start_element = root.find('.//call-action[@id="2"]')

# Get the parent node of the starting element
parent_node = start_element.getparent()

# Option 1: Get all sibling elements (including the start element)
all_siblings = list(parent_node)

# Option 2: Get all siblings EXCEPT the start element
siblings_excluding_start = [elem for elem in parent_node if elem is not start_element]

# Option 3: Get only same-type siblings
same_type_siblings = [elem for elem in parent_node if elem.tag == start_element.tag]

Each of these approaches gives you flexibility depending on your exact use case. Pick the one that fits how you're interacting with the XML!

内容的提问来源于stack exchange，提问作者Lju