Check if array element exists in string

Question

I thought this would be a simple thing to do with a native php function but i've found a few different, all quite complicated, ways that people have tried to achieve it. What's the most efficient way of checking if a string contains one or more elements in an array? i.e, below - where $data['description'] is a string. Obv the in_array check below breaks because it expects param 2 to be an array

$keywords = array(
            'bus',
            'buses',
            'train',
    );

    if (!in_array($keywords, $data['description']))
            continue;

Answer 1

Assuming that the String is a collapsed/delimited list of values

function arrayInString( $inArray , $inString , $inDelim=',' ){
  $inStringAsArray = explode( $inDelim , $inString );
  return ( count( array_intersect( $inArray , $inStringAsArray ) )>0 );
}

Example 1:

arrayInString( array( 'red' , 'blue' ) , 'red,white,orange' , ',' );
// Would return true
// When 'red,white,orange' are split by ',',
// the 'red' element matched the array

Example 2:

arrayInString( array( 'mouse' , 'cat' ) , 'mouse' );
// Would return true
// When 'mouse' is split by ',' (the default deliminator),
// the 'mouse' element matches the array which contains only 'mouse'

Assuming that the String is plain text, and you are simply looking for instances of the specified words inside it

function arrayInString( $inArray , $inString ){
  if( is_array( $inArray ) ){
    foreach( $inArray as $e ){
      if( strpos( $inString , $e )!==false )
        return true;
    }
    return false;
  }else{
    return ( strpos( $inString , $inArray )!==false );
  }
}

Example 1:

arrayInString( array( 'apple' , 'banana' ) , 'I ate an apple' );
// Would return true
// As 'I ate an apple' contains 'apple'

Example 2:

arrayInString( array( 'car' , 'bus' ) , 'I was busy' );
// Would return true
// As 'bus' is present in the string, even though it is part of 'busy'

Answer 2

You can do this using regular expressions -

if( !preg_match( '/(\b' . implode( '\b|\b', $keywords ) . '\b)/i', $data['description'] )) continue;

the result regexp will be /(\bbus\b|\bbuses\b|\btrain\b)/