xmltodict.py 文件源码

def _emit(key, value, content_handler,
          attr_prefix='@',
          cdata_key='#text',
          root=True,
          preprocessor=None):
    if preprocessor is not None:
        result = preprocessor(key, value)
        if result is None:
            return
        key, value = result
    if not isinstance(value, (list, tuple)):
        value = [value]
    if root and len(value) > 1:
        raise ValueError('document with multiple roots')
    for v in value:
        if v is None:
            v = OrderedDict()
        elif not isinstance(v, dict):
            v = _unicode(v)
        if isinstance(v, _basestring):
            v = OrderedDict(((cdata_key, v),))
        cdata = None
        attrs = OrderedDict()
        children = []
        for ik, iv in list(v.items()):
            if ik == cdata_key:
                cdata = iv
                continue
            if ik.startswith(attr_prefix):
                attrs[ik[len(attr_prefix):]] = iv
                continue
            children.append((ik, iv))
        content_handler.startElement(key, AttributesImpl(attrs))
        for child_key, child_value in children:
            _emit(child_key, child_value, content_handler,
                  attr_prefix, cdata_key, False, preprocessor)
        if cdata is not None:
            content_handler.characters(cdata)
        content_handler.endElement(key)