新人问题，xml提取字段值

breeze7086

lst name="jvm">
<str name="version">20.1-b02</str>
<str name="name">Java HotSpot(TM) 64-Bit Server VM</str>
<int name="processors">16</int>
−
<lst name="memory">
<str name="free">15.1 GB</str>
<str name="total">23.1 GB</str>
<str name="max">23.1 GB</str>
<str name="used">8 GB (%34.</str>
−
<lst name="raw">
<long name="free">16172727968</long>
<long name="total">24803016704</long>
<long name="max">24803016704</long>
<long name="used">8630288736</long>
<double name="used%">34.795318807361795</double>
</lst>
</lst>

这是打开网页后的一段XML数据，不是本地xml文件
现在我想用python提取出memory字段下，free total max used这几个值
请问该怎么做
一头雾水
感谢！！

iamacnhero

使用 xml.etree.ElementTree 模块，find “/lst", 然后再 find "free total max used", 取出text即可。

ubuntu_mark

回复 1# breeze7086


     建议你可以看看minidom库，处理xml数据的方法
   里边很很多方法
   比如，你取到那个节点，然后循环取里边的数据（.data方法）

breeze7086

能来点实际代码我参考不
感激不尽

iamacnhero

能来点实际代码我参考不
感激不尽
breeze7086 发表于 2011-06-21 16:32

把要解析的XML传一点可用的上来

breeze7086

<response>
−
<lst name="responseHeader">
<int name="status">0</int>
<int name="QTime">5</int>
</lst>
−
<lst name="core">
<str name="schema">patsnapV5.0</str>
<str name="host">solr-sh-02.patsnap.com</str>
<date name="now">2011-06-21T13:50:59.34Z</date>
<date name="start">2011-06-20T14:10:01.453Z</date>
−
<lst name="directory">
<str name="cwd">/solr/patents5.0/patsnapIndex</str>
<str name="instance">/solr/patsnapIndex/core0</str>
<str name="data">/solr/patsnapIndex/data</str>
<str name="index">/solr/patents5.0/patsnapIndex/data/index</str>
</lst>
</lst>
−
<lst name="lucene">
<str name="solr-spec-version">4.0.0.2011.06.15.16.38.04</str>
−
<str name="solr-impl-version">
4.0-SNAPSHOT ${svnversion} - Administrator - 2011-06-15 16:38:04
</str>
<str name="lucene-spec-version">4.0-SNAPSHOT</str>
<str name="lucene-impl-version">4.0-SNAPSHOT ${svnversion} - 2011-06-15 16:38:57</str>
</lst>
−
<lst name="jvm">
<str name="version">20.1-b02</str>
<str name="name">Java HotSpot(TM) 64-Bit Server VM</str>
<int name="processors">16</int>
−
<lst name="memory">
<str name="free">15.1 GB</str>
<str name="total">23.1 GB</str>
<str name="max">23.1 GB</str>
<str name="used">8 GB (%34.</str>
−
<lst name="raw">
<long name="free">16172727968</long>
<long name="total">24803016704</long>
<long name="max">24803016704</long>
<long name="used">8630288736</long>
<double name="used%">34.795318807361795</double>
</lst>
</lst>
−
<lst name="jmx">
−
<str name="bootclasspath">
/usr/java/jdk1.6.0_26/jre/lib/resources.jar:/usr/java/jdk1.6.0_26/jre/lib/rt.jar:/usr/java/jdk1.6.0_26/jre/lib/sunrsasign.jar:/usr/java/jdk1.6.0_26/jre/lib/jsse.jar:/usr/java/jdk1.6.0_26/jre/lib/jce.jar:/usr/java/jdk1.6.0_26/jre/lib/charsets.jar:/usr/java/jdk1.6.0_26/jre/lib/modules/jdk.boot.jar:/usr/java/jdk1.6.0_26/jre/classes
</str>
<str name="classpath">/solr/solr-tomcat/bin/bootstrap.jar</str>
−
<arr name="commandLineArgs">
−
<str>
-Djava.util.logging.config.file=/solr/solr-tomcat/conf/logging.properties
</str>
<str>-Xmx26214m</str>
<str>-Xms26214m</str>
<str>-Xmn20g</str>
<str>-XX:MaxPermSize=2g</str>
−
<str>
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
</str>
<str>-Xmx26214m</str>
<str>-Xms26214m</str>
<str>-Xmn20g</str>
<str>-XX:MaxPermSize=2g</str>
<str>-Djava.endorsed.dirs=/solr/solr-tomcat/endorsed</str>
<str>-Dcatalina.base=/solr/solr-tomcat</str>
<str>-Dcatalina.home=/solr/solr-tomcat</str>
<str>-Djava.io.tmpdir=/solr/solr-tomcat/temp</str>
</arr>
<date name="startTime">2011-06-20T14:09:58.541Z</date>
<long name="upTimeMS">85260800</long>
</lst>
</lst>
−
<lst name="system">
<str name="name">Linux</str>
<str name="version">2.6.18-238.el5</str>
<str name="arch">amd64</str>
<double name="systemLoadAverage">0.08</double>
−
</lst>
</response>

iamacnhero

我用了你这个XML的一小段：

1. <response>
   
2. <lst name="responseHeader">
   
3. <int name="status">0</int>
   
4. <int name="QTime">5</int>
   
5. </lst>
   
6. <lst name="jvm">
   
7. <str name="version">20.1-b02</str>
   
8. <str name="name">Java HotSpot(TM) 64-Bit Server VM</str>
   
9. <int name="processors">16</int>
   
10. </lst>
    
11. <lst name="memory">
    
12. <str name="free">15.1 GB</str>
    
13. <str name="total">23.1 GB</str>
    
14. <str name="max">23.1 GB</str>
    
15. <str name="used">8 GB</str>
    
16. </lst>
    
17. </response>
    

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解析代码：

1. # -*- encoding: utf-8 -*-
   
2. 
   
3. from xml.etree import ElementTree
   
4. 
   
5. def main():
   
6.     xml = "t.xml"
   
7. 
   
8.     jvm = ElementTree.parse(xml)
   
9.     for i in jvm.findall('/lst'):
   
10.             if i.get("name") == "jvm":
    
11.                     print "Version: %s" % i.findall("str")[0].text
    
12.                     print "Name: %s" % i.findall("str")[1].text
    
13.                     print "Processors: %s" % i.find("int").text
    
14. 
    
15. if __name__ == '__main__':
    
16.     main()
    

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xiaomayi0323

返回的XML：

1. <user><id>10116</id><email>aa@aa.com</email><nickname>唐僧他妈</nickname><signature>故宫里都是太监吗？</signature><avatar>/users/10116/headIcon/1304911263052.jpg</avatar><avatar_thumb>/users/10116/headIcon/1304911263052_thumb.jpg</avatar_thumb><gender>0</gender><birthday>1985-03-23</birthday><age>26</age><score>2543</score><status>0</status><createTime>1297934782000</createTime><loginTime>1308728311000</loginTime><mediaSize>53</mediaSize><eventsSize>18</eventsSize><followsSize>71</followsSize><friendsSize>159</friendsSize><footprintsSize>25</footprintsSize><location><coordinate><latitude>34.225624</latitude><longitude>108.876226</longitude></coordinate></location><tags>80后</tags><settings><touch>0</touch><footprint>0</footprint><encounter>0</encounter></settings></user>

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python代码：

1. #! /usr/bin/env python
   
2. #coding=utf-8
   
3. import urllib
   
4. from xml.etree import ElementTree
   
5. 
   
6. def main():
   
7.     f = urllib.urlopen("http://172.16.220.166:8080/doudouy/api/v2/users/10116")
   
8.     xml = f.read()
   
9. 
   
10.     jvm = ElementTree.parse(xml)
    
11.     for i in jvm.findall('/user'):
    
12.             print i.find("int").text
    
13. 
    
14. if __name__ == '__main__':
    
15.     main()
    

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执行后的错误信息：

> "C:\Python25\pythonw.exe" -u "E:\python\Practise\0622\test xml.py"
Traceback (most recent call last):
  File "E:\python\Practise\0622\test xml.py", line 15, in <module>
    main()
  File "E:\python\Practise\0622\test xml.py", line 10, in main
    jvm = ElementTree.parse(xml)
  File "C:\Python25\lib\xml\etree\ElementTree.py", line 862, in parse
    tree.parse(source, parser)
  File "C:\Python25\lib\xml\etree\ElementTree.py", line 579, in parse
    source = open(source, "rb")
IOError: [Errno 2] No such file or directory: '<?xml version="1.0" encoding="UTF-8" standalone="yes"?><user><id>10116</id><email>aa@aa.com</email><nickname>\xe5\x94\x90\xe5\x83\xa7\xe4\xbb\x96\xe5\xa6\x88</nickname><signature>\xe6\x95\x85\xe5\xae\xab\xe9\x87\x8c\xe9\x83\xbd\xe6\x98\xaf\xe5\xa4\xaa\xe7\x9b\x91\xe5\x90\x97\xef\xbc\x9f</signature><avatar>/users/10116/headIcon/1304911263052.jpg</avatar><avatar_thumb>/users/10116/headIcon/1304911263052_thumb.jpg</avatar_thumb><gender>0</gender><birthday>1985-03-23</birthday><age>26</age><score>2543</score><status>0</status><createTime>1297934782000</createTime><loginTime>1308728311000</loginTime><mediaSize>53</mediaSize><eventsSize>18</eventsSize><followsSize>71</followsSize><friendsSize>159</friendsSize><footprintsSize>25</footprintsSize><location><coordinate><latitude>34.225624</latitude><longitude>108.876226</longitude></coordinate></location><tags>80\xe5\x90\x8e</tags><settings><touch>0</touch><footprint>0</footprint><encounter>0</encounter></settings></user>'

必须要保存成文件才可以吗？

106033177

回复 8# xiaomayi0323
http://effbot.org/zone/pythondoc ... Tree.parse-function
arse(source, parser=None)
    Parses an XML document into an element tree.
    source
        A filename or file object containing XML data.
    parser
        An optional parser instance. If not given, the standard XMLTreeBuilder parser is used.
    Returns:
        An ElementTree instance

字符串的话

1. xml="""
   
2.     <response>
   
3.     <lst name="responseHeader">
   
4.     <int name="status">0</int>
   
5.     <int name="QTime">5</int>
   
6.     </lst>
   
7.     </response>
   
8.     """
   
9. jvm = ElementTree.XML(xml)
   
10. for i in jvm.findall('lst'):
    
11.     print i.findall('int')[0].text  
    

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