php man page for preg_split

PREG_SPLIT(3)								 1							     PREG_SPLIT(3)

preg_split - Split string by a regular expression

SYNOPSIS
       array preg_split (string  $pattern, string  $subject, [int  $limit = -1], [int  $flags])

DESCRIPTION
	Split the given string by a regular expression.

PARAMETERS
	      o $pattern
		- The pattern to search for, as a string.

	      o $subject
		- The input string.

	      o $limit
		-  If  specified, then only substrings up to $limit are returned with the rest of the string being placed in the last substring. A
		$limit of -1, 0 or NULL means "no limit" and, as is standard across PHP, you can use NULL to skip to the $flags parameter.

	      o $flags
		-$flags can be any combination of the following flags (combined with the | bitwise operator):

		     o PREG_SPLIT_NO_EMPTY - If this flag is set, only non-empty pieces will be returned by preg_split(3).

		     o PREG_SPLIT_DELIM_CAPTURE - If this flag is set, parenthesized expression in the delimiter  pattern  will  be  captured  and
		       returned as well.

		     o PREG_SPLIT_OFFSET_CAPTURE  -  If  this  flag  is  set,  for  every occurring match the appendant string offset will also be
		       returned. Note that this changes the return value in an array where every element is an array  consisting  of  the  matched
		       string at offset 0 and its string offset into $subject at offset 1.

RETURN VALUES
	Returns an array containing substrings of $subject split along boundaries matched by $pattern.

EXAMPLES
       Example #1

	      preg_split(3) example : Get the parts of a search string

	      <?php
	      // split the phrase by any number of commas or space characters,
	      // which include " ", 
, 	, 
 and f
	      $keywords = preg_split("/[s,]+/", "hypertext language, programming");
	      print_r($keywords);
	      ?>

	      The above example will output:

	      Array
	      (
		  [0] => hypertext
		  [1] => language
		  [2] => programming
	      )

       Example #2

	      Splitting a string into component characters

	      <?php
	      $str = 'string';
	      $chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY);
	      print_r($chars);
	      ?>

	      The above example will output:

	      Array
	      (
		  [0] => s
		  [1] => t
		  [2] => r
		  [3] => i
		  [4] => n
		  [5] => g
	      )

       Example #3

	      Splitting a string into matches and their offsets

	      <?php
	      $str = 'hypertext language programming';
	      $chars = preg_split('/ /', $str, -1, PREG_SPLIT_OFFSET_CAPTURE);
	      print_r($chars);
	      ?>

	      The above example will output:

	      Array
	      (
		  [0] => Array
		      (
			  [0] => hypertext
			  [1] => 0
		      )

		  [1] => Array
		      (
			  [0] => language
			  [1] => 10
		      )

		  [2] => Array
		      (
			  [0] => programming
			  [1] => 19
		      )

	      )

NOTES
       Tip

	       If  you	don't  need  the  power  of  regular  expressions,  you can choose faster (albeit simpler) alternatives like explode(3) or
	      str_split(3).

       Tip

	       If matching fails, an array with a single element containing the input string will be returned.

SEE ALSO
       PCRE Patterns, preg_quote(3), implode(3), preg_match(3), preg_match_all(3), preg_replace(3), preg_last_error(3).

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