Question

I am working with some code in PHP that grabs the referrer data from a search engine, giving me the query that the user entered.

I would then like to remove certain stop words from that string if they exist. However, the word may or may not have a space at either end.

For example, I have been using str_replace to remove a word as follows:

$keywords = str_replace("for", "", $keywords);
$keywords = str_replace("sale", "", $keywords);

but if the $keywords value is “baby formula” it will change it to “baby mula” – removing the “for” part.

Without having to create further str_replace’s that account for ” for” and “for ” – is there a preg_replace type command I could use that would remove the given word if it is found with a space at either end?

My idea would be to put all of the stop words into an array and step through them that way and I suspect that a preg_replace is going to be quicker than stepping through multiple str_replace lines.

UPDATE:
Solved thanks to you guys using the following combination:

$keywords = "...";
$stopwords = array("for","each");
foreach($stopwords as $stopWord)
{
    $keywords = preg_replace("/(\b)$stopWord(\b)/", "", $keywords);   
}

Answer 1

$keywords = "...";
$stopWords = array("for","sale");
foreach($stopWords as $stopWord){
    $keywords = preg_replace("/(\b)$stopWord(\b)/", "", $keywords);
}