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<tbody> glitch in PHP Simple HTML DOM parser

Posted by: admin July 12, 2020 Leave a comment

Questions:

I’m using PHP Simple HTML DOM Parser to scrape some data of a webshop (also running XAMPP 1.7.2 with PHP5.3.0), and I’m running into problems with <tbody> tag. The structure of the table is, essentialy (details aren’t really that important):

<table>
  <thead>
    <!--text here-->
  </thead>
  <tbody>
    <!--text here-->
  </tbody>
</table>

Now, I’m trying to get to the <tbody> section by using code:

$element = $html->find('tbody',0)->innertext;

It doesn’t throw any errors, it just prints nothing out when I try to echo it. I’ve tested the code on other elements, <thead>, <table>, even something like <span class="price"> and they all work fine (ofcourse, removing “,0” fails the code). They all give their correct sections. Outertext ditto. But it all fails on <tbody>.

Now, I’ve skimmed through the Parser, but I’m not sure I can figure it out. I’ve noticed that <thead> isn’t even mentioned, but it works fine. shrug

I guess I could try and do child navigation, but that seems to glitch as well. I’ve just tried running:

$el = $html->find('table',0);
$el2 = $el->children(2);
echo $el2->outertext;

and no dice. Tried replacing children with first_child and 2 with 1, and still no dice. Funny, though, if I try ->find instead of children, it works perfectly.

I’m pretty confident I could find a work-around the whole thing, but this behaviour seems odd enough to post here. My curious mind is happy for all the help it can get.

How to&Answers:

in simple_html_dom.php file comment or remove line #396

// if ($m[1]==='tbody') continue;

Answer:

There is a bug report for this issue here:
http://sourceforge.net/p/simplehtmldom/bugs/79/

It is still open at the time of this writing. There is an alternative fix if you do not wish to modify the source code, for example in a loop to find <tr>‘s

<?php
  // The *BROKEN* way to find the <tr>'s 
  // below the <tbody> below the <table id="foo">
  foreach($dom->find('tbl#foo tbody tr') as $tr) {
    /* you will get nothing */
  }

You can instead selectively check the parent tag name while iterating all <tr>‘s like so:

<?php
  // A workaround to find the <tr>'s 
  // below the <tbody> below the <table id="foo">
  foreach($dom->find('tbl#foo tr') as $tr) { // note the lack of tbody selector
    /* you will get all trs, but let's only work with ones with the parent
       of a tbody! */
    if($tr->parent->tag == 'tbody') { // our workaround
      /* this part will work as you would expect the above broken code to work */
    }
  }

Also note, a slightly unrelated issue that I ran into, that Chrome and FF inspectors will correct tag soup regarding<tbody> and <thead>. Be careful — only look at the actual source — stay away from the DOM inspectors if you run into unexplainable issues.

Answer:

Make sure your tbody is coming from some javascript execution. I was facing the same problem with a span tag. Later I found that, if any html code is getting into the page via jquery/any other javascript execution then in that case simple_html_dom simply fails.

Answer:

Make sure that tbody is really is there. Many browsers will add a tbody to tables in the inspect panel even though they are not present in the response.