Question

I have a PHP search script that queries a MySQL database and then parses the results through HTML to allow CSS styling. I want the script to highlight all of the keywords in the results that the user has search for. How can I do this with PHP?

My PHP script is:

<?php

mysql_connect("localhost","username","password");
mysql_select_db("database");

if(!empty($_GET['q'])){
$query=mysql_real_escape_string(trim($_GET['q']));
$searchSQL="SELECT * FROM links WHERE `title` LIKE '%{$query}%'  LIMIT 8";
$searchResult=mysql_query($searchSQL);

while ($row=mysql_fetch_assoc($searchResult)){
    $results[]="<a href='{$row['url']}' class='webresult'><div class='title'>{$row['title']}</div><div class='desc'>{$row['description']}</div><div class='url'>{$row['url']}</div></a>";
}

if(empty($results)){
echo 'No results were found';
} else {
echo implode($results);
}
}

?>

Answer 1

Simplistically you could adapt the loop here:

$searchvar = trim($_GET['q']);
while ($row=mysql_fetch_assoc($searchResult)){
    $description = str_replace($searchvar, '<span class="highlight">'.$searchvar."</span>", $row['description']);
    $results .="<a href='{$row['url']}' class='webresult'>
    <div class='title'>{$row['title']}</div>
    <div class='desc'>{$description}</div>
    <div class='url'>{$row['url']}</div></a>";
}

To make it a little better:

$searchvar = explode(" ", trim($_GET['q'])); //puts each space separated word into the array.      
while ($row=mysql_fetch_assoc($searchResult)){
    $description = $row['description'];
    foreach($searchvar as $var) $description = str_replace($var, '<span class="highlight">'.$var."</span>", $description);
    $description = str_replace($searchvar, '<span class="highlight">'.$searchvar."</span>", $row['description']);
    $results .="<a href='{$row['url']}' class='webresult'>
    <div class='title'>{$row['title']}</div>
    <div class='desc'>{$description}</div>
    <div class='url'>{$row['url']}</div></a>";
}

The benefit of the second one there is that if a user types in “ipod toudch yellow” you will be searching for “ipod”, “toudch” and “yellow” which would negate the type and make the results more general.

You would need to exchange the single:

like '%query%'

with

foreach(explode(" ", trim($_GET['q']) as $searchvar) $where[] = "like '%$searchvar%'";
$wheresql = implode(" OR ", $where);

to get each search “word” to be looked for in the sql or you will have a limited search with a unrelated highlight.