Python ElementTree XML API与子元素不匹配

我正在尝试使用USPS API返回包跟踪的状态。我有一个返回ElementTree.Element对象的方法，该对象是根据USPSAPI返回的XML字符串构建的

这是返回的XML字符串

<?xml version="1.0" encoding="UTF-8"?>
  <TrackResponse>
    <TrackInfo ID="EJ958088694US">
      <TrackSummary>The Postal Service could not locate the tracking information for your 
       request. Please verify your tracking number and try again later.</TrackSummary>
    </TrackInfo>
  </TrackResponse>

现在我可以在xml字符串中看到标记“TrackSummary”存在，我希望能够使用ElementTree的find方法访问它

作为额外的证明，我可以迭代响应对象并证明“TrackSummary”标记存在

for item in response.iter():
    print(item, item.text)

返回：

<Element 'TrackResponse' at 0x00000000041B4B38> None
<Element 'TrackInfo' at 0x00000000041B4AE8> None
<Element 'TrackSummary' at 0x00000000041B4B88> The Postal Service could not locate the tracking information for your request. Please verify your tracking number and try again later.

返回

None

我是不是遗漏了什么？看起来我应该可以毫无问题地找到子元素

方法

.find（）

只搜索下一层，而不是递归搜索。要递归搜索，需要使用XPath查询。在XPath中，双斜杠

/

是一种递归搜索。试试这个：

# returns a list of elements with tag TrackSummary
response.xpath('//TrackSummary')

# returns a list of the text contained in each TrackSummary tag
response.xpath('//TrackSummary/node()')

.find（）

方法只搜索下一层，而不是递归。要递归搜索，需要使用XPath查询。在XPath中，双斜杠

/

是一种递归搜索。试试这个：

# returns a list of elements with tag TrackSummary
response.xpath('//TrackSummary')

# returns a list of the text contained in each TrackSummary tag
response.xpath('//TrackSummary/node()')

选择所有子元素。例如，*/egg选择所有名为egg的孙子

element = response.findall('*/TrackSummary') # you will get a list
print element[0].text #fast print else iterate the list

>>> The Postal Service could not locate the tracking informationfor your request. Please verify your tracking number and try again later.

选择所有子元素。例如，*/egg选择所有名为egg的孙子

element = response.findall('*/TrackSummary') # you will get a list
print element[0].text #fast print else iterate the list

>>> The Postal Service could not locate the tracking informationfor your request. Please verify your tracking number and try again later.

element = response.findall('*/TrackSummary') # you will get a list
print element[0].text #fast print else iterate the list

>>> The Postal Service could not locate the tracking informationfor your request. Please verify your tracking number and try again later.