Question

How can i extract the portion of a string giving the beginning and the end position?

I know there is a method called substr() but is not what im looking for (the third parameter is lenght of the portion..)

Answer 1

If you have the start and end positions, the length is just end – start:

$string = "The quick brown fox jumped over the lazy dog";
$start = 4;
$end = 15;
substr($string, $start, $end - $start); //=> "quick brown"

See this in action at http://www.ideone.com/LRfYT.