format search results.

[letimati]

Hi I want to format the way I output search results by showing the string query inside <em></em> tags and cut it so shows this in the middle of 20 characters.

So if i have

$text = "this is the test text i have but i dont want to output it all so just want to output the important part of the text";

$strignQuery = 'text';

So the output would be

...the test <em>text</em> i have but i... ...part of the <em>text</em>...

My thoughts so far are to string replace the 'text' with '<em>text</em>' easy then i thought if there was a way to do a split it on this with a 10 character on each way then just output the results that would work well. However i am sure there is a more elegant way of doing this.

Thanks in advance for any help

 

[DRJ478]

This can turn into a complicated topic - would you want to highlight the text even if it is a partial match, e.g. if "text" were inside a word like batextender?

Anyway, I would recommend to use a PCRE (Perl COmpatible Regular Expression) to handle this. Have a look at preg_replace http://www.php.net/preg_replace.

If you need help with the expression, let us know.

 

[letimati]

I would like that to be matched as well.

I have done something like this so far

$noTags = strip_tags($text);
$withEm = str_replace($_GET['sq'], '<em>'.$_GET['sq'].'</em>', $noTags);
print '<p>'.substr($withEm, 0 , 100).'...</p>';
$pos = strrpos($withEm, $_GET['sq']);
if (!($pos === false)){
print '<p>...'.substr($withEm, ($pos - 35), ($pos + 35)).'...</p>';
}

does not really work but I will keep mucking about with it.

 

[DRJ478]

I had written (a long time ago) a function for highlighting that could be used:

/**
 * FUNCTION highlight
 * Highlights search terms in an HTML or plain string
 *
 * @param $searchwords string The terms that will be split on spaces into individual words
 * @param $subject string The haystack, may be HTML or plain string
 * 
 * @return $string The manipulated output with all tags reassembled
 */
function highlight($searchwords,$subject) {
        $searchStr = preg_replace('/ /','|',$searchwords);

        /* split the plain text from the HTML */
        $text = preg_split("/([<].*?[>])/",$subject);
        preg_match_all("/([<].*?[>])/",$subject,$tags);

        $result = '';

        /* now replace the searchwords with word+markup */
        foreach ($text as $key=>$value) {
                $text[$key] = preg_replace("/($searchStr)/i",'<span class="highlight">'."\\1".'</span>',$value);
        }

        /* reduce to full matches */
        $tags = $tags[0];

        /* reassemble the string */
        for ($i=0;$i<=count($tags);$i++){
                $result .= $text[$i].$tags[$i];
        }
        return($result);
}

It actually uses CSS markup rather than an <em> tag, but you can easily adapt that.