使用lxml.etree移动整个元素 [英] Move an entire element in with lxml.etree

问题描述

在lxml中，是否有可能赋予元素将整个内容移到xml文档中的其他位置，而不必读取所有子元素并重新创建它的原因?我最好的例子是改变父母.我在文档周围翻来翻去，但是运气不高.预先感谢！

Within lxml, is it possible, given an element, to move the entire thing elsewhere in the xml document without having to read all of it's children and recreate it? My best example would be changing parents. I've rummaged around the docs a bit but haven't had much luck. Thanks in advance!

推荐答案

.append，.insert和其他操作默认情况下会这样做

.append, .insert and other operations do that by default

>>> from lxml import etree
>>> tree = etree.XML('<a><b><c/></b><d><e><f/></e></d></a>')
>>> node_b = tree.xpath('/a/b')[0]
>>> node_d = tree.xpath('/a/d')[0]
>>> node_d.append(node_b)
>>> etree.tostring(tree) # complete 'b'-branch is now under 'd', after 'e'
'<a><d><e><f/></e><b><c/></b></d></a>'
>>> node_f = tree.xpath('/a/d/e/f')[0] # Nothing stops us from moving it again
>>> node_f.append(node_a) # Now 'a' is deep under 'f'
>>> etree.tostring(tree)
'<a><d><e><f><b><c/></b></f></e></d></a>'

在移动带有尾部文本的节点时要小心.在lxml中，尾文本属于该节点并随其移动. (此外，当您删除节点时，其尾部文本也会被删除)

Be careful when moving nodes having a tail text. In lxml tail text belong to the node and moves around with it. (Also, when you delete a node, its tail text is also deleted)

>>> tree = etree.XML('<a><b><c/></b>TAIL<d><e><f/></e></d></a>')
>>> node_b = tree.xpath('/a/b')[0]
>>> node_d = tree.xpath('/a/d')[0]
>>> node_d.append(node_b)
>>> etree.tostring(tree)
'<a><d><e><f/></e><b><c/></b>TAIL</d></a>'

有时候这是理想的效果，但是有时您会需要这样的东西:

Sometimes it's a desired effect, but sometimes you will need something like that:

>>> tree = etree.XML('<a><b><c/></b>TAIL<d><e><f/></e></d></a>')
>>> node_b = tree.xpath('/a/b')[0]
>>> node_d = tree.xpath('/a/d')[0]
>>> node_a = tree.xpath('/a')[0]
>>> # Manually move text
>>> node_a.text = node_b.tail
>>> node_b.tail = None
>>> node_d.append(node_b)
>>> etree.tostring(tree)
>>> # Now TAIL text stays within its old place
'<a>TAIL<d><e><f/></e><b><c/></b></d></a>'

这篇关于使用lxml.etree移动整个元素的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！