How can I parse HTML in batches using xpath [PHP]? - php

Question

I tried all sorts of things but couldn't find a solution.
I want to retrieve elements from html code using xpath in php.
Ex:
<div class='student'>
<div class='name'>Michael</div>
<div class='age'>26</div>
</div>
<div class='student'>
<div class='name'>Joseph</div>
<div class='age'>27</div>
</div>
I want to retrieve the information and put them in an array as follows:
$student[0][name] = Michael;
$student[0][age] = 26;
$student[1][name] = Joseph;
$student[1][age] = 27;`
In other words i want the matching ages to stay with the names.
I tried the following:
$dom = new DOMDocument();
$dom->loadHTML($html);
$xpathDom = new DomXPath($dom);
$homepostcontentNodes = $xpathDom->query("//*[contains(#class, 'student')]//*[contains(#class, 'name')]");`
However, this is only grabbing me the nodes 'names'
How can i get the matching age nodes?

Answer 1

Of course it is only grabbing the nodes name - you are telling it to!
What you will need to do is in two steps:
Pick out all the student nodes
For each student node, pick out the columns
This is a pretty standard step in linearization of data, and the XPath queries are simple:
Step 1
You pretty much have it:
$studentNodes = $xpathDom->query("//div[contains(#class, 'student')]");
This will return all your student nodes.
Step 2
This is where the magic happens. We have our nodes, we can loop through them (DOMNodeList implements Iterator, so we can foreach-loop through them). What we need to figure out is how to find its children...
...Oh wait. DOMNode implements a method called getNodePath which returns the full, direct XPath path to the node. This allows us to then simply append /div to get all the div direct descendents to the node!
Another quick foreach, and we get this code:
$studentNodes = $xpathDom->query("//div[contains(#class, 'student')]");
$result = array();
foreach ($studentNodes as $v) {
// Child nodes: student
$r = array();
$columns = $xpathDom->query($v->getNodePath()."/div");
foreach ($columns as $v2) {
// Attributes allows me to get the 'class' property of the node. Bit clunky, but there's no alternative
$r[$v2->attributes->getNamedItem("class")->textContent] = $v2->textContent;
}
$result[] = $r;
}
var_dump($result);
Full fiddle: http://codepad.viper-7.com/t868Wh