function.str_highlight.php
Highlight a string in text without corrupting HTML tags
- Author: Aidan Lister <aidan@php.net>
- Version: 3.1.1
- Link: http://aidanlister.com/repos/v/function.str_highlight.php
- Return: Text with needle highlighted
- Views: 25659
- Downloads: 1678
Source
<?php
/**
* Perform a simple text replace
* This should be used when the string does not contain HTML
* (off by default)
*/
define('STR_HIGHLIGHT_SIMPLE', 1);
/**
* Only match whole words in the string
* (off by default)
*/
define('STR_HIGHLIGHT_WHOLEWD', 2);
/**
* Case sensitive matching
* (off by default)
*/
define('STR_HIGHLIGHT_CASESENS', 4);
/**
* Overwrite links if matched
* This should be used when the replacement string is a link
* (off by default)
*/
define('STR_HIGHLIGHT_STRIPLINKS', 8);
/**
* Highlight a string in text without corrupting HTML tags
*
* @author Aidan Lister <aidan@php.net>
* @version 3.1.1
* @link http://aidanlister.com/repos/v/function.str_highlight.php
* @param string $text Haystack - The text to search
* @param array|string $needle Needle - The string to highlight
* @param bool $options Bitwise set of options
* @param array $highlight Replacement string
* @return Text with needle highlighted
*/
function str_highlight($text, $needle, $options = null, $highlight = null)
{
// Default highlighting
if ($highlight === null) {
$highlight = '<strong>\1</strong>';
}
// Select pattern to use
if ($options & STR_HIGHLIGHT_SIMPLE) {
$pattern = '#(%s)#';
$sl_pattern = '#(%s)#';
} else {
$pattern = '#(?!<.*?)(%s)(?![^<>]*?>)#';
$sl_pattern = '#<a\s(?:.*?)>(%s)</a>#';
}
// Case sensitivity
if (!($options & STR_HIGHLIGHT_CASESENS)) {
$pattern .= 'i';
$sl_pattern .= 'i';
}
$needle = (array) $needle;
foreach ($needle as $needle_s) {
$needle_s = preg_quote($needle_s);
// Escape needle with optional whole word check
if ($options & STR_HIGHLIGHT_WHOLEWD) {
$needle_s = '\b' . $needle_s . '\b';
}
// Strip links
if ($options & STR_HIGHLIGHT_STRIPLINKS) {
$sl_regex = sprintf($sl_pattern, $needle_s);
$text = preg_replace($sl_regex, '\1', $text);
}
$regex = sprintf($pattern, $needle_s);
$text = preg_replace($regex, $highlight, $text);
}
return $text;
}
?>
Example
<pre>
<?php
require_once 'function.str_highlight.php';
// Simple Example
$string = 'This is a site about PHP and SQL';
$search = array('php', 'sql');
echo str_highlight($string, $search);
echo "\n";
// With HTML in the text
$string = 'Link to <a href="php">php</a>';
$search = 'php';
echo htmlspecialchars(str_highlight($string, $search));
echo "\n";
// Matching whole words only
$string = 'I like to eat bananas with my nana!';
$search = 'Nana';
echo str_highlight($string, $search, STR_HIGHLIGHT_SIMPLE|STR_HIGHLIGHT_WHOLEWD);
echo "\n";
// With custom highlighting
$string = 'With custom highlighting!';
$search = 'custom';
$highlight = '<span style="text-decoration: underline;">\1</span>';
echo str_highlight($string, $search, STR_HIGHLIGHT_SIMPLE, $highlight);
echo "\n";
// With links
$string = 'I am a <a href="http://www.php.net">link</a>';
$search = 'link';
$highlight = '<a href="http://www.google.com/">\1</a>';
echo htmlspecialchars(str_highlight($string, $search, STR_HIGHLIGHT_STRIPLINKS, $highlight));
?>
</pre>
Output
This is a site about PHP and SQL
Link to <a href="php"><strong>php</strong></a>
I like to eat bananas with my nana!
With custom highlighting!
I am a <a href="http://www.google.com/">link</a>
Comments