Get element content if text exists next to it - php

Question

I have this HTML in $string:
$string = '<p>random</p>
Test 1 (target1)
<br>
Test 2 (target1)
<br>
Test 3 (skip)
// etc
';
And I have a few terms in $array:
$array = array(
'(target1)',
'(target2)'
);
How can I search through $string to find all terms in $array and grab the content of the <a> tag that precedes it?
So I end up with the following results:
$results = array(
array(
'text' => 'Test 1',
'needle' => 'target1'
),
array(
'text' => 'Test 2',
'needle' => 'target1'
)
);

Answer 1

I will give you an answer using javascript, but php can do the same thing.
You can search through the array 1 string at a time, and finish once no results are found and you have reached the end of your array.
target1Match = s.match(/<.+?>(.+?)<\/.+?> *\(target1\)/);
// target1Match is now [Test 1 (target1), Test 1]
target1Match = target1Match[1];
target2Match = s.match(/<.+?>(.+?)<\/.+?> *\(target2\)/);
// target1Match is now [Test 2 (target2), Test 2]
target2Match = target2Match[1];
You build the regex using variables for "target1 and 2"
matching multiple targets and specific tag
s.match(/<a.+?>(.+?)<\/a> *\((target1|target2)\)/);

Answer 2

Using preg_match_all():
// Assuming your HTML as $str, your terms as $terms
$results = [];
foreach ($terms as $t) {
// Get content of <a> tag preceeding the term
preg_match_all('/<a ?.*>(.*)<\/a>\s+' . preg_quote($t) . '/', $str, $matches);
//Then insert into your result array
foreach ($matches[1] as $m) {
$results[] = [
'text' => $m,
'needle' => $t
];
}
}
Output:
// echo '<pre>' . print_r($results, true) . '</pre>';
Array
(
[0] => Array
(
[text] => Test 1
[needle] => (target1)
)
[1] => Array
(
[text] => Test 2
[needle] => (target1)
)
)
See also: preg_quote()

Answer 3

I'm in the JayBlanchard camp. Here's a solution that rightly uses DomDocument & Xpath with a dynamically generated query to target <a> tags that are immediately followed by text that contains one of the qualifying needles.
For the sample needles, this is the generated query:
//a[following-sibling::text()[1][contains(.,'(target1)') or contains(.,'(target2)')]]
Code: (Demo)
$html = '<p>random</p>
Test 1 (skip)
<br>
Test 2 (target1)
<br>
Test 3 (target1)
<br>
Test 4 (skip)
<br>
Test 5 (target2)
<br>
Test 6 (skip)
';
$needles = [
'(target1)',
'(target2)'
];
$contains = array_reduce($needles, function($carry, $needle) {
return $carry .= ($carry !== null ? ' or ' : '') . "contains(.,'$needle')";
});
$matches = [];
$dom=new DOMDocument;
$dom->loadHTML($html);
$xpath = new DOMXPath($dom);
foreach ($xpath->query("//a[following-sibling::text()[1][$contains]]") as $node) {
$matches[] = ["text" => $node->nodeValue, "needle" => trim($node->nextSibling->nodeValue)];
}
var_export($matches);
Output:
array (
0 =>
array (
'text' => 'Test 2',
'needle' => '(target1)',
),
1 =>
array (
'text' => 'Test 3',
'needle' => '(target1)',
),
2 =>
array (
'text' => 'Test 5',
'needle' => '(target2)',
),
)