From: Alex Stahl <astahl@...5.com>
Date: 2010-10-06T05:53:02+09:00
Subject: Re: How can I count number of elements in an HTML page

Nokogiri allows direct access to HTML elements as data.  I use it a lot
in my work.  Try something like:

require 'nokogiri'
page = Nokogiri::HTML response.body
count = 0
page.xpath("//div[@class='first section']).each do |element|
  count += 1 if element.xpath("/ul")
end

Or something along those lines... (I didn't test this first).


On Tue, 2010-10-05 at 15:45 -0500, Paul wrote:
> Hi there, I'm using net/http to retrieve some html pages and now I
> want to count the number of items in a list on the page.  The
> response.body is stored as a string.
> 
> The HTML looks something like this:
> ----
> <div class="first section">
>    <h1>
>       Section Heading I'm interested in:
>    </h1>
>    <ul>
>       <li>
>          <form action="foo" method="post" name="">
>            <button type="submit">foo</button>
>          </form>
>       </li>
>       <li>
>          <form action="bar" method="post" name="">
>             <button type="submit">bar</button>
>          </form>
>       </li>
>    </ul>
> </div>
> 
> <div class="next section">
> ----
> 
> So what I want to do is count the number of li's in a particular div
> section.  In this case the answer is 2. It might be more, it might be
> 0.
> 
> I can find the section I want with a regex but I don't know how to
> iterate through the string looking for particular elements.  I was
> thinking about taking the section I'm interested in and saving it as
> an array and then iterating through each array element (html line)
> that way, but I thought there might be a quicker way to do it.
> 
> suggestions?
> 
> TIA
>