Ruby Mechanize屏幕抓取帮助 [英] Ruby Mechanize screen scraping help

问题描述

我正在尝试在带有日期的表格中抓取一行.我只想抓取具有今天日期的第三行.

I am trying to scrape a row in a table with a date. I want to scrape only the third row that have the date today.

这是我的机械化代码.我试图选择今天有日期及其列的列女巫:

This is my mechanize code. I am trying to select the colum row witch have the date today and its and its columns:

agent.page.search("//td").map(&:text).map(&:strip)

agent.page.search("//td").map(&:text).map(&:strip)

Output:
"11-02-2011", "1", "1", "1", "1", "0", "0,00 DKK", "0,00", "0,00 DKK", 
"12-02-2011", "5", "5", "1", "4", "0", "0,00 DKK", "0,00", "0,00 DKK", 
"14-02-2011", "1", "3", "1", "1", "0", "0,00 DKK", ",00", "0,00 DKK",
"7", "9", "3", "6", "0", "0,00 DKK", "0,00", "0,00 DKK

"

我只想抓取今天的第三行.

I want to only scrape the third row that is the date today.

推荐答案

不是使用'//td'遍历<td>标记，而是搜索<tr>标记，仅获取第三个，然后遍历.

Rather than loop over the <td> tags using '//td', search for the <tr> tags, grab only the third one, then loop over '//td'.

Mechanize在内部使用Nokogiri，所以这是使用Nokogiri-ese的方法:

Mechanize uses Nokogiri internally, so here's how to do it in Nokogiri-ese:

html = <<EOT
<table>
<tr><td>11-02-2011</td><td>1</td><td>1</td><td>1</td><td>1</td><td>0</td><td>0,00 DKK</td><td>0,00</td><td>0,00 DKK</td></tr>
<tr><td>12-02-2011</td><td>5</td><td>5</td><td>1</td><td>4</td><td>0</td><td>0,00 DKK</td><td>0,00</td><td>0,00 DKK</td></tr>
<tr><td>14-02-2011</td><td>1</td><td>3</td><td>1</td><td>1</td><td>0</td><td>0,00 DKK</td><td>,00</td><td>0,00 DKK</td></tr>
</table>
EOT

require 'nokogiri'
require 'pp'

doc = Nokogiri::HTML(html)

pp doc.search('//tr')[2].search('td').map{ |n| n.text }

>> ["14-02-2011", "1", "3", "1", "1", "0", "0,00 DKK", ",00", "0,00 DKK"]

使用机械化agent.page所附的.search('//tr')[2].search('td').map{ |n| n.text }，如下所示:

Use the .search('//tr')[2].search('td').map{ |n| n.text } appended to Mechanize's agent.page, like so:

agent.page.search('//tr')[2].search('td').map{ |n| n.text }

自从我与《机械化》一起玩已经有一段时间了，所以它也可能是agent.page.parser....

It's been a while since I played with Mechanize, so it might also be agent.page.parser....

表中将有更多行.我要抓取的行始终是倒数第二个.

there will come more rows in the table. The row that i want to scrape is always the second last.

将这些信息放入您的原始问题很重要.您的问题越准确，我们的答案就越准确.

It's important to put that information into your original question. The more accurate your question, the more accurate our answers.

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