lxml。物化真的很简单。

以示例文本为例:

from lxml import objectify
from collections import defaultdict

count = defaultdict(int)

root = objectify.fromstring(text)

for item in root.bar.type:
    count[item.attrib.get("foobar")] += 1

print dict(count)

输出:

{'1': 1, '2': 1}

#If the xml is in the form of a string as shown below then
from lxml  import etree, objectify
'''sample xml as a string with a name space {http://xmlns.abc.com}'''
message =b'<?xml version="1.0" encoding="UTF-8"?>\r\n<pa:Process xmlns:pa="http://xmlns.abc.com">\r\n\t<pa:firsttag>SAMPLE</pa:firsttag></pa:Process>\r\n'  # this is a sample xml which is a string


print('************message coversion and parsing starts*************')

message=message.decode('utf-8') 
message=message.replace('<?xml version="1.0" encoding="UTF-8"?>\r\n','') #replace is used to remove unwanted strings from the 'message'
message=message.replace('pa:Process>\r\n','pa:Process>')
print (message)

print ('******Parsing starts*************')
parser = etree.XMLParser(remove_blank_text=True) #the name space is removed here
root = etree.fromstring(message, parser) #parsing of xml happens here
print ('******Parsing completed************')


dict={}
for child in root: # parsed xml is iterated using a for loop and values are stored in a dictionary
    print(child.tag,child.text)
    print('****Derving from xml tree*****')
    if child.tag =="{http://xmlns.abc.com}firsttag":
        dict["FIRST_TAG"]=child.text
        print(dict)


### output
'''************message coversion and parsing starts*************
<pa:Process xmlns:pa="http://xmlns.abc.com">

    <pa:firsttag>SAMPLE</pa:firsttag></pa:Process>
******Parsing starts*************
******Parsing completed************
{http://xmlns.abc.com}firsttag SAMPLE
****Derving from xml tree*****
{'FIRST_TAG': 'SAMPLE'}'''

我推荐ElementTree。同样的API还有其他兼容的实现，比如lxml和Python标准库中的cElementTree;但是，在这种情况下，他们主要增加的是更快的速度——编程的容易程度取决于ElementTree定义的API。

首先从XML中构建一个Element实例根，例如使用XML函数，或者通过解析文件，例如:

import xml.etree.ElementTree as ET
root = ET.parse('thefile.xml').getroot()

或者在ElementTree中显示的许多其他方法中的任何一种。然后这样做:

for type_tag in root.findall('bar/type'):
    value = type_tag.get('foobar')
    print(value)

输出:

1
2

simplified_scrapy:一个新的库，我使用后就爱上了它。我向你推荐。

from simplified_scrapy import SimplifiedDoc
xml = '''
<foo>
   <bar>
      <type foobar="1"/>
      <type foobar="2"/>
   </bar>
</foo>
'''

doc = SimplifiedDoc(xml)
types = doc.selects('bar>type')
print (len(types)) # 2
print (types.foobar) # ['1', '2']
print (doc.selects('bar>type>foobar()')) # ['1', '2']

这里有更多的例子。这个库很容易使用。

为了简单起见，我建议使用xmltodict。

它将XML解析为OrderedDict;

>>> e = '<foo>
             <bar>
                 <type foobar="1"/>
                 <type foobar="2"/>
             </bar>
        </foo> '

>>> import xmltodict
>>> result = xmltodict.parse(e)
>>> result

OrderedDict([(u'foo', OrderedDict([(u'bar', OrderedDict([(u'type', [OrderedDict([(u'@foobar', u'1')]), OrderedDict([(u'@foobar', u'2')])])]))]))])

>>> result['foo']

OrderedDict([(u'bar', OrderedDict([(u'type', [OrderedDict([(u'@foobar', u'1')]), OrderedDict([(u'@foobar', u'2')])])]))])

>>> result['foo']['bar']

OrderedDict([(u'type', [OrderedDict([(u'@foobar', u'1')]), OrderedDict([(u'@foobar', u'2')])])])

你可以使用BeautifulSoup:

from bs4 import BeautifulSoup

x="""<foo>
   <bar>
      <type foobar="1"/>
      <type foobar="2"/>
   </bar>
</foo>"""

y=BeautifulSoup(x)
>>> y.foo.bar.type["foobar"]
u'1'

>>> y.foo.bar.findAll("type")
[<type foobar="1"></type>, <type foobar="2"></type>]

>>> y.foo.bar.findAll("type")[0]["foobar"]
u'1'
>>> y.foo.bar.findAll("type")[1]["foobar"]
u'2'