Python元素树XML解析

我正在尝试解析一个xml文件，该文件是通过使用AdobePro将pdf导出为XML1.0得到的。 我正在使用Python和ElementTree进行解析。 pdf包含一个跨多页的表，该表具有多个不同的表头

我想从表格中解析和提取行和列数据，表格以包含特定字符串（如MECHANICAL）的标题开始，并停在下一个表格标题部分（如COMPLETED）。从而排除本节前后的所有行和列数据。没有容易解析的标记，标记模式只是重复

以下是我当前的python代码：

# Python

import sys
import re     # regular expression
import xml.etree.ElementTree as xml

tree = xml.parse("C:/Documents and Settings/alilly.CORPORATE/Desktop/python xml parse/excerpt.xml")

print "=================== Find Columns ===================="    

for node in tree.iter('TR'):

    print "tag=",node.tag

    count = len(node.getiterator('TD'))

    #if count != 10:
    #    continue

    print "------------"

    for col in node.getiterator('TD'):
        print "      tag=",col.tag, "attrib=", col.attrib, "text=", col.text


print "=================== Find Headers ===================="

# find headers
for node in tree.iter('ImageData'):
    print "figure text = ", node.tail

这是我的XML文件：

<?xml version="1.0" encoding="UTF-8" ?>
<!-- Created from PDF via Acrobat SaveAsXML -->
<!-- Mapping Table version: 28-February-2003 -->
<TaggedPDF-doc>
<?xpacket begin='?' id='W5M0MpCehiHzreSzNTczkc9d'?>
<?xpacket begin="?" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 4.2.1-c041 52.342996, 2008/05/07-20:48:00        ">
   <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:Description rdf:about=""
            xmlns:pdf="http://ns.adobe.com/pdf/1.3/">
         <pdf:Producer>GPL Ghostscript 8.70</pdf:Producer>
         <pdf:Keywords/>
      </rdf:Description>
      <rdf:Description rdf:about=""
            xmlns:xmp="http://ns.adobe.com/xap/1.0/">
         <xmp:ModifyDate>2011-03-01T09:36:13-05:00</xmp:ModifyDate>
         <xmp:CreateDate>2011-03-01T09:36:13-05:00</xmp:CreateDate>
         <xmp:CreatorTool>PDFCreator Version 1.0.2</xmp:CreatorTool>
      </rdf:Description>
      <rdf:Description rdf:about=""
            xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/">
         <xmpMM:DocumentID>d417764e-466c-11e0-0000-f7ea6a538d79</xmpMM:DocumentID>
         <xmpMM:InstanceID>uuid:0c6ada50-6db0-4d59-88e1-fc23aa6ebc14</xmpMM:InstanceID>
      </rdf:Description>
      <rdf:Description rdf:about=""
            xmlns:dc="http://purl.org/dc/elements/1.1/">
         <dc:format>xml</dc:format>
         <dc:title>
            <rdf:Alt>
               <rdf:li xml:lang="x-default">my pdf file</rdf:li>
            </rdf:Alt>
         </dc:title>
         <dc:creator>
            <rdf:Seq>
               <rdf:li>ltamm</rdf:li>
            </rdf:Seq>
         </dc:creator>
         <dc:description>
            <rdf:Alt>
               <rdf:li xml:lang="x-default"/>
               <rdf:li xml:lang="x-repair"/>
            </rdf:Alt>
         </dc:description>
      </rdf:Description>
   </rdf:RDF>
</x:xmpmeta>
<?xpacket end="w"?>
<?xpacket end='r'?>
<Part>
<H1>Misc </H1>
<Sect>
<H3>This is a test </H3>
<Sect>
<H5>Deletions </H5>
<L>
<LI>
<LI_Title>Special codes </LI_Title>
</LI>
</L>
<Figure>
<ImageData src=""/>
</Figure>
<Figure>
<ImageData src=""/>
Main INTERIOR </Figure>
<Table>
<TR>
<TH>S = Standard O = Optional </TH>
</TR>
<TR>
<TD><Figure>
<ImageData src=""/>
</Figure>
</TD>
<TD>S </TD>
</TR>
</Table>
<Figure>
<ImageData src=""/>
This is the MECHANICAL header</Figure>
<Table>
<TR>
<TH>S = Standard O = Optional </TH>
</TR>
<TR>
<TH>Free Flow </TH>
<TD>Ref. Code </TD>
<TD>DESCRIPTION </TD>
<TD>Rooster </TD>
<TD>747 Dog </TD>
<TD>888 Rabbit </TD>
</TR>
<TR>
<TD>xxx GOgo xxB </TD>
<TD>Beany xxx </TD>
<TD>nothing here xxx </TD>
<TD>xxx B </TD>
<TD>snake ddd </TD>
<TD>Cow fff </TD>
<TD>eee </TD>
</TR>
<TR>
<TH/>
<TD/>
<TD>Squirrel Protection </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
</TR>
<TR>
<TH/>
<TD>J77 </TD>
<TD>Rocket Launcher </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
</TR>
<TR>
<TH/>
<TD/>
<TD>Lunch </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
<TD>S </TD>
</TR>
<TR>
<TH/>
<TD>Jss5 </TD>
<TD>Now is the time for all good men </TD>
<TD>-</TD>
<TD>A1 </TD>
<TD>A1 </TD>
<TD>-</TD>
<TD>-</TD>
<TD>-</TD>
<TD>-</TD>
</TR>
<TR>
<TD>Capacity </TD>
<TD/>
<TD>2/3 </TD>
<TD>2/3 </TD>
<TD>2/3 </TD>
</TR>
</Table>
<Figure>
<ImageData src=""/>
Final COMPLETED PAGE 1 OF 2 </Figure>
<Figure>
<ImageData src=""/>
</Figure>
<P>Graphite </P>
<P>painted fun </P>
<P>Control yourself </P>
<Figure>
<ImageData src=""/>
Meaningless Header PAGE 2 OF 2 </Figure>
<Figure>
<ImageData src=""/>
</Figure>
<P>)multi-coat </P>
<P>front</P>
<P>single-slot system </P>
<Figure>
<ImageData src=""/>
Almost Done Header PAGE 1 OF 1 </Figure>
<Figure>
<ImageData src=""/>
</Figure>
<Figure>
<ImageData src=""/>
</Figure>
<Figure>
<ImageData src=""/>
</Figure>
<P>Snow Blizzard. </P>
<P>Done </P>
</Sect>
</Sect>
</Part>
</TaggedPDF-doc>

---

在需要保持状态的情况下，我会使用SAX风格的XML解析器，下面是一个示例脚本，它简单地将行拉入机械图形和完成图形之间

#!python
import xml.sax
import xml.sax.handler

class Handler(xml.sax.handler.ContentHandler):
    def __init__(self):
        self.l_ch = list()
        self.__in_mechanical = False

    def startElement(self, name, attrs):
        if name == 'TR':
            self.l_rows = list()

    def characters (self, ch):
        self.l_ch += ch

    def endElement(self, name):
        if self.l_ch:
            ch = ''.join(self.l_ch).strip()

        if name == 'Figure':
            if ch.find('MECHANICAL') >= 0:
                self.__in_mechanical = True
            elif ch.find('COMPLETED') >= 0:
                self.__in_mechanical = False

        elif name == 'TD' and self.__in_mechanical:
            self.l_rows.append(ch)

        elif name == 'TR' and self.__in_mechanical:
            print 'Row:', self.l_rows
            self.l_rows = list()

        self.l_ch = list()

parser = xml.sax.make_parser()
parser.setContentHandler(Handler())
parser.parse(open('sample.xml'))

这给了我以下结果，应该会让你变得更复杂

Row: []
Row: [u'Ref. Code', u'DESCRIPTION', u'Rooster', u'747 Dog', u'888 Rabbit']
Row: [u'xxx GOgo xxB', u'Beany xxx', u'nothing here xxx', u'xxx B', u'snake ddd', u'Cow fff', u'eee']
Row: [u'', u'Squirrel Protection', u'S', u'S', u'S', u'S', u'S', u'S', u'S']
Row: [u'J77', u'Rocket Launcher', u'S', u'S', u'S', u'S', u'S', u'S', u'S']
Row: [u'', u'Lunch', u'S', u'S', u'S', u'S', u'S', u'S', u'S']
Row: [u'Jss5', u'Now is the time for all good men', u'-', u'A1', u'A1', u'-', u'-', u'-', u'-']
Row: [u'Capacity', u'', u'2/3', u'2/3', u'2/3']

---

从你的描述中不清楚你到底想选择什么。 听起来像是要处理 包含机械和已完成字符串的元素。 在本例中，这只是一个表，但我假设它可能是 任意数量的表

如果可以使用lxml，那么可以使用xpath进行选择

from lxml import etree
x = etree.parse( file('mech.xml'))
# select Tables following "MECHANICAL" :
fol = x.xpath( '//Figure[contains(., "MECHANICAL")]/following-sibling::Table[1]' )
# [<Element Table at 101532ec0>]
# select Tables preceding "COMPLETED" :
pre = x.xpath( '//Figure[contains(.,"COMPLETED")]/preceding-sibling::Table' )
# [<Element Table at 101532d08>, <Element Table at 101532ec0>]
# get their intersection:
tables = [ e for e in fol if e in pre ]
for t in tables:
     for tr in t.xpath( 'TR' ):
         # [ ... process ... ] 

---

将xml.etree.ElementTree作为xml导入是个坏主意；您刚刚删除了标准xml包的名称空间。最好将其作为ET或与已知包或模块名称不冲突的内容导入。