Match part of string with part of other string

Question

I working on a simple search function where I want to match a part of a string with part of another string.

Example: The search term is: fruitbag I want to match the product: fruit applebag

I want to create something so that the system matches:

• fruitbag
• fruit applebag

Or even "fruit" and "bag".

In summary; parts inside a string need to match with parts inside the search term. Is this possible?

    $products = array(
        'fruit applebag',
        'pinapple',
        'carrots',
        'bananas',
        'coconut oil',
        'cabbage',
    );

    if( ! empty( $_POST['search'] ) ) {

        $s = $_POST['search'];
        $results = array();
        foreach( $products as $index => $product ) {

            if( preg_match( '/' . $s . '.*/i', $product, $matched ) ) {
                $results[] = $matched[0];
            }
        }
        print_r($results); 
        // This only returns fruit applebag if the search term is something like "fruit ap"
    }

Answer 1

Use something like this (split the searched word into two parts and look for a match thas has characters between those two parts):

$products = array(
        'fruit applebag',
        'pinapple',
        'carrots',
        'bananas',
        'coconut oil',
        'cabbage',
    );
$s = 'fruitbag';
$results = array();
foreach( $products as $index => $product ) {
    for($i=1;$i<strlen($s);$i++){
        if(preg_match( '/' . substr($s,0,$i) . '.*'.substr($s,$i+1).'/i', $product, $matched ) ) {
            $results[] = $matched[0];
        }
    }
}
print_r($results);

Output:

Array ( [0] => fruit applebag [1] => fruit applebag )

Answer 2

It is possible, but could be very costly. As stated, your requirement is that any substring of the search term is potentially relevant. So take fruitbag and generate a list of all substrings:

f,r,u,i,t,b,a,g,fr,ru,ui,it,tb,ba,ag,fru,rui,uit,...,bag,...,fruit,...,fruitbag

But you probably don't want that any word with the letter a be a match. So a first approach could be to specify a minimum number of letters (e.g. 3), which will significantly limit the potential matches. But even then... Does it make sense to match fru, or rui?

A better approach would be to use a dictionary, to extract actual words or syllables from your search string. (In your case, extract fruit and bag from fruitbag).

You can find an English dictionary fairly easily.