How can I split a string in PHP at the nth occurrence of a needle?

Question

There must be a fast and efficient way to split a (text) string at the "nth" occurrence of a needle, but I cannot find it. There is a fairly full set of functions

Answer 1

This is ugly, but it seems to work:

$foo = '1 2 3 4 5 6 7 8 9 10 11 12 13 14';

$parts = preg_split('!([^ ]* [^ ]* [^ ]*) !', $foo, -1,
            PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);

var_dump($parts);

Output:

array(5) {
  [0]=>
  string(5) "1 2 3"
  [1]=>
  string(5) "4 5 6"
  [2]=>
  string(5) "7 8 9"
  [3]=>
  string(8) "10 11 12"
  [4]=>
  string(5) "13 14"
}

Replace the single spaces in the query with a single character you wish to split on. This expression won't work as-is with multiple characters as the delimiter.

This is hard coded for every third space. With a little tweaking, probably could be easily adjusted. Although a str_repeat to build a dynamic expression would work as well.