PHP中的正则表达式模式\ K替代品

Question

I've been using \K quite a lot but recently realized that it does not work in PHP below v5.2.4. So I'm looking for a different way.

<?php
    $html = '<div>hello</div>
        <div class="someclass">hi</div>
        <div class="sample">this text should be included</div>
        <div>bye</div>
    ';
    // $pattern = '/<div.+class=["\']sample["\'].+div>\K/i'; // <-- this doesn't work below v5.2.4
    $pattern = '/(?<=<div.+class=["\']sample["\'].+div>)/i'; // causes an error.
    $array = preg_split($pattern, $html);
    print_r($array);
?>

I've seen somewhere (?<=) can be used as the alternative and I tried it but it causes an error. Any suggestion?

Answer 1

Okay, found a workaround. preg_split() accepts the PREG_SPLIT_DELIM_CAPTURE flag in the fourth parameter so the matching string can be included in the delimited elements of array. I just need to pick one additional element to extract the strings and it is not that much work to do.

<?php
    $html = '<div>hello</div>
        <div class="someclass">hi</div>
        <div class="sample">this text should be included</div>
        <div>bye</div>
    ';
    $pattern = '/(<div.+class=["\']sample["\'].+div>)\${0}/i'; 
    $array = preg_split($pattern, $html, null, PREG_SPLIT_DELIM_CAPTURE);
    print_r($array);
?>