Dynamically highly text on a webpage

var the_text = "On the Insert tab, the galleries include items that are designed to coordinate with the overall look of your document. You can use these galleries to insert tables, headers, footers, lists, cover pages, and other document building blocks. When you create pictures, charts, or diagrams, they also coordinate with your current document look. <span class="myquote">"In some urban classrooms, children arrive without any notion of sharing behavior. If they have grown up as street survivors, without strong early  mediation for sharing, they may come to school ready to do battle to the death” (Rodriguez and Bellanca 135).</span> You can easily change the formatting of selected text in the document text by choosing a look for the selected text from the Quick Styles gallery on the Home tab. You can also format text directly by using the other controls on the Home tab. Most controls offer a choice of using the look from the current theme or using a format that you specify directly."

Select allOpen in new window

<?php // demo/temp_smanyx.php
/**
 * https://www.experts-exchange.com/questions/28947809/Dynamically-highly-text-on-a-webpage.html
 *
 * Getting started in PHP:
 * https://www.experts-exchange.com/articles/11769/And-by-the-way-I-am-New-to-PHP.html
 */
error_reporting(E_ALL);

// WHAT WE ARE LOOKING FOR, AND WHERE WE ARE LOOKING
$signal_string    = '"In some urban classrooms, children arrive without any notion of sharing behavior. If they have grown up as street survivors, without strong early mediation for sharing, they may come to school ready to do battle to the death" (Rodriguez and Bellanca 135).';
$rest_of_the_text = 'On the Insert tab, the galleries include items that are designed to coordinate with the overall look of your document. You can use these galleries to insert tables, headers, footers, lists, cover pages, and other document building blocks. When you create pictures, charts, or diagrams, they also coordinate with your current document look. "In some urban classrooms, children arrive without any notion of sharing behavior. If they have grown up as street survivors, without strong early mediation for sharing, they may come to school ready to do battle to the death" (Rodriguez and Bellanca 135). You can easily change the formatting of selected text in the document text by choosing a look for the selected text from the Quick Styles gallery on the Home tab. You can also format text directly by using the other controls on the Home tab. Most controls offer a choice of using the look from the current theme or using a format that you specify directly.';

// SHOW THE TEST DATA
echo PHP_EOL . "SIGNAL STRING:<br>";
echo PHP_EOL . $signal_string;
echo PHP_EOL . '<br>';

echo PHP_EOL . "REST OF THE TEXT:<br>";
echo PHP_EOL . $rest_of_the_text;
echo PHP_EOL . '<br>';

// PROCESS THE TEXT TO HIGHLIGHT THE SINGAL STRING
$arr = explode($signal_string, $rest_of_the_text);
$glu = '<b>' . $signal_string . '</b>';
$new = implode($glu, $arr);

echo PHP_EOL . "AFTER PROCESSING:<br>";
echo PHP_EOL . $new;

Select allOpen in new window

text.find(summary)

Select allOpen in new window

beginning = text.find(summary)
end = beginning + len(summary)
highlight = text[beginning:end]

Select allOpen in new window