Highlighting multiple search terms.

[ptowndesign]

I've got a function that highlights single search terms (ex. "animal"). Problem is that when someone adds multiple terms the only word that is highlighted is the last (ex. "animal farm" only farm is bolded). Any thoughts on how I can loop the bolding process for multiple search terms.

Current Function:
// ##################### highlight_search_criteria ##################
function highlight_search_criteria($search_results, $search_criteria) {
if (empty($search_criteria)) {
return $search_results;
} else {

    $start_tag = "<b>"; 
    $end_tag = "</b>"; 

    $highlighted_results = $start_tag . $search_criteria . $end_tag; 

    return eregi_replace($search_criteria, $highlighted_results, $search_results); 
} 

}

[HP400]

I would use preg_replace . Its faster and should replace all the matching patterns.