PHP：在特定词组/单词之后搜索文本文件并输出

<?php
$lines = file(\'my-text-file.txt\');

foreach ($lines as $line_num => $line) {
    echo \"Line #<b>{$line_num}</b> : \" . htmlspecialchars($line) . \"<br />\\n\";
}
?>  

function search ( $what = array (), $filePath ) {
    $lines = file ( $filePath );

    foreach ( $lines as $num => $line ) {
        foreach ( $what as $needle ) {
            $pos = strripos ( $line, $needle );
            if ( $pos !== false ) {
                echo \"Line #<b>{$num}</b> : \" . htmlspecialchars($line) . \"<br />\\n\";
            }
        }
    }
}

#   Usage:
$what = array ( \'The horse is white\', \'The flower is yellow\', \'mixed\' );
search ( $what );