regular expresion find characters and replace php code example

Example 1: php preg replace

preg_replace($pattern, $replacement, $subject [, $limit [, &$count]]);
// Returns an array if the subject parameter is an array,
// or a string otherwise.
// If matches are found, the new subject will be returned, otherwise
// subject will be returned unchanged or NULL if an error occurred.

Example 2: php preg_replace function

preg_replace($pattern, $replacement, $string);