相对xpath php

Question

I'm parsing html that looks like this:

  <table class="linesTbl">
        <tr class="linesHeader">
            <td><h3>EventName</h3></td>
        </tr><tr class="linesColumns">
            <td>Date</td><td class="contestLine">Description</td>
        </tr><tr class="linesAlt1">
            <td>Time</td><td>X1</td><td>Price1</td>
        </tr><tr class="linesAlt1">
            <td>&nbsp;</td><td>X2</td><td>Price2</td></tr>
</table>

There are multiple tables like this so I'm trying to loop through them and grab all of the data. I'm not sure how xpath handles queries in php. Currently I'm just trying to extract the EventName from each table.

$doc = new DOMDocument();
@$doc->loadHTML($html);
$xpath = new DOMXPath($doc);

foreach ($xpath->query("//table[@class = 'linesTbl']") as $tableNode){

  $headerTag = $xpath->query(".//h3", $tableNode);
  echo $headerTag->nodeValue;

}

For the $headerTag query I also tried query("./tr/td/h3", $tableNode). How do I go about doing this relative query?

Answer 1

Your xpath expression is relative already:

$headerTag = $xpath->query(".//h3", $tableNode);
                            ^       ^^^^^^^^^^
                            |    relative-to node
                       relative path

However, this returns a nodelist, not a single node, so if you do:

echo $headerTag->item(0)->nodeValue;
               ^^^^^^^^^

You can access the element you want, see the output:

EventName

I hope this is helpful.