我在XML中有很多行,我试图获得一个特定节点属性的实例。
<foo>
<bar>
<type foobar="1"/>
<type foobar="2"/>
</bar>
</foo>
我如何访问属性foobar的值?在这个例子中,我想要“1”和“2”。
我在XML中有很多行,我试图获得一个特定节点属性的实例。
<foo>
<bar>
<type foobar="1"/>
<type foobar="2"/>
</bar>
</foo>
我如何访问属性foobar的值?在这个例子中,我想要“1”和“2”。
当前回答
#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'}'''
其他回答
为了增加另一种可能性,可以使用untangle,因为它是一个简单的xml-to-python-object库。这里有一个例子:
安装:
pip install untangle
用法:
你的XML文件(有一点变化):
<foo>
<bar name="bar_name">
<type foobar="1"/>
</bar>
</foo>
使用untangle访问属性:
import untangle
obj = untangle.parse('/path_to_xml_file/file.xml')
print obj.foo.bar['name']
print obj.foo.bar.type['foobar']
输出将是:
bar_name
1
更多关于untangle的信息可以在“untangle”中找到。
此外,如果您感兴趣,可以在“Python和XML”中找到使用XML和Python的工具列表。您还将看到前面的答案中提到的最常见的问题。
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'
如果你使用python-benedict,就不需要使用lib特定的API。只需从XML初始化一个新实例并轻松管理它,因为它是dict子类。
安装很简单:pip install python-benedict
from benedict import benedict as bdict
# data-source can be an url, a filepath or data-string (as in this example)
data_source = """
<foo>
<bar>
<type foobar="1"/>
<type foobar="2"/>
</bar>
</foo>"""
data = bdict.from_xml(data_source)
t_list = data['foo.bar'] # yes, keypath supported
for t in t_list:
print(t['@foobar'])
它支持并规范化多种格式的I/O操作:Base64, CSV, JSON, TOML, XML, YAML和查询字符串。
它在GitHub上经过了很好的测试和开源。披露:我是作者。
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
#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'}'''