通过lxml python更改xml中的属性值

Question

这是我的xml：

<request><table attributeA="50" attributeB="1"></table>........</request>

如何更新attributeA的值，以获得类似attributeA =“456”

的内容

<request><table attributeA="456" attributeB="1"></table>........</request>

Answer 1

使用etree和xpath：

>>> from lxml import etree
>>> xml = '<request><table attributeA="50" attributeB="1"></table></request>'
>>> root = etree.fromstring(xml)
>>> for el in root.xpath("//table[@attributeA]"):
...     el.attrib['attributeA'] = "456"
...
>>> print etree.tostring(root)
<request><table attributeA="456" attributeB="1"/></request>