Question

$test = array('<h1>text1</h1>','<h1><a href="#">text2</a><h1>','<h1>text3</h1><p>subtext3</p>');

In a long long texts, I use preg_split cut them into small pieces. I want to remove only h1 tag wraped and without hyperlink.

I hope remove all the text looks like: <h1>text1</h1> //only h1 wraped and without hyperlink.

And remain <h1><a href="#">text2</a><h1>,<h1>text3</h1><p>subtext3</p>

Answer 1

Use a loop to go through each array element and find each instance of the string “<“. Then look at the next 3 characters. If they’re “h1>” then you you have the correct tag. If you ever find a “<” that has a different 3 characters, then its not an “” HTML tag and you can remove this array object.

To remove the given object from the array, you can use unset($array[$index]) and when you’re done I recommend using a sort to remove any index skips that may occur.

You’ll want to use functions such as strpos to get the position of a string, and substr to get a subset of the given string. php.net is your friend 🙂

Here is an example function which works with your $test array:

<?php
$test = array('<h1>text1</h1>','<h1><a href="#">text2</a><h1>','<h1>text3</h1><p>subtext3</p>');
function removeBadElements(&$array) {
    foreach($array as $k => $v) {
        // $v is a single array element
        $offset = 0;
        do {
            $pos = strpos($v, '<', $offset);
            $offset = $pos + 1;
            if($pos === false) { break; }

            $tag = substr($v, $pos, 3);
            $next = substr($v, $pos+1, 1);
            if($next == '/') { continue; }
            if($tag == '<h1') { continue; }
            else {
                unset($array[$k]);
                break;
            }
        } while($offset + 2 < strlen($v));
    }
}
echo "\nORIG ARRAY:\n";
print_r($test);
removeBadElements($test);
echo "\n\n-------\nMODIFIED ARRAY:\n\n";
print_r($test);
?>