python和XML:如何将两个文档放在一个文档中

Question

这是我的代码:

def extract_infos(i):
    blabla...
    blabla calculate v...
    dom = xml.dom.minidom.parseString(v)
    return dom

doc = xml.dom.minidom.Document()
for i in range(1,100):
    dom = extract_infos(i)
    for child in dom.childNodes:
        doc.appendChild(child.cloneNode(True))

最后两行工作一次:

Traceback (most recent call last):
  File "./c.py", line 197, in <module>
    doc.appendChild(child.cloneNode(True))
  File "/usr/lib/python2.6/xml/dom/minidom.py", line 1552, in appendChild
    "two document elements disallowed")
xml.dom.HierarchyRequestErr: two document elements disallowed

所以我的问题是:如何将两个现有文档放入一个新文档中(将每个文档的根元素放入一个新的,首要的根元素中).

Answer 1

以下是使用minidom将XML文档附加到单个主根元素的方法.

from xml.dom import minidom, getDOMImplementation

XML1 = """
<sub1>
 <foo>BAR1</foo>
</sub1>"""

XML2 = """
<sub2>
 <foo>BAR2</foo>
</sub2>"""

impl = getDOMImplementation()
doc = impl.createDocument(None, "root", None)

for s in [XML1, XML2]:
    elem = minidom.parseString(s).firstChild
    doc.firstChild.appendChild(elem)

print doc.toxml()

=>

<?xml version="1.0" ?><root><sub1>
 <foo>BAR1</foo>
</sub1><sub2>
 <foo>BAR2</foo>
</sub2></root>

由于附加Document对象不起作用,firstChild因此用于获取顶层Element.