Python ElementTree XML 解析
我正在尝试解析一个XML文件，这个文件是我用Adobe Pro把PDF导出成XML 1.0格式得到的。 我使用Python和ElementTree来进行解析。这个PDF里有一个跨越多页的表格，并且有几个不同的表头。
我想从这个表格中提取行和列的数据，提取的起点是包含特定字符串的表头（比如“MECHANICAL”），终点是下一个表头部分（比如“COMPLETED”）。这样就可以排除这个部分之前和之后的所有行和列数据。可惜的是，没有简单的标签可以用来解析，这些标签的模式只是重复出现。
这是我现在的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>
2 个回答
0
从你的描述来看，想要选择的内容不是很清楚。听起来你是想处理包含“MECHANICAL”和“COMPLETED”这两个字符串之间的所有元素。 （在这个例子中，只有一个表格，但我猜可能会有任意数量的表格。）
如果你可以使用lxml这个库，你可以通过xpath来进行选择。
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 ... ]
4
在需要保持状态的情况下，我会使用一种叫做SAX的XML解析器。下面是一个示例脚本，它可以简单地提取你在“MECHANICAL”和“COMPLETED”之间的行。
#!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'))
这个脚本会给我以下结果，应该能帮助你开始处理更复杂的内容。
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']