$re = '/(?<=EREF\+|MREF\+|CRED\+|SVWZ\+|ABWA\+)(.+?)(?=EREF\+|MREF\+|CRED\+|SVWZ\+|ABWA\+|$)/';
$str = 'EREF+012345678901234MREF+ABCDEF01234567890123CRED+DE12ABC01234567890SVWZ+ABCEDFG HIJ 01234567890 123,45ABWA+ABCDEFGHIJKLMNOPQR';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php