Is it possible for xpath to return NULL if there is no text data? -


i trying extract data table. table data rows formatted <td headers="h1" align="left"></td> when there no data.

using etree.tostring() method lxml library prints out these elements <td headers="h1" align="left"/> instead of source formatting.

furthermore, using xpath if run code tree.path('//td[@headers="h1"]/text()') resulting list not include blank values there no data.

as trying write these results csv file, how include null, i.e. "" when there no data?

one workaround use //td[@headers="h1"] xpath elements , .text property on each:

from lxml import etree  data = """ <table>     <tr>         <td headers="h1" align="left"></td>         <td headers="h1" align="left">text1</td>         <td headers="h1" align="left"/>         <td headers="h1" align="left">text2</td>         <td headers="h1" align="left"></td>     </tr> </table> """  tree = etree.fromstring(data) print [element.text element in tree.xpath('//td[@headers="h1"]')]

prints:

[none, 'text1', none, 'text2', none]

if want empty string instead of none:

print [element.text if element.text not none else ''        element in tree.xpath('//td[@headers="h1"]')]

would print:

['', 'text1', '', 'text2', '']

also see: how return '' empty node's text() in xpath?


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