(PHP 5 >= 5.2.0, PHP 7)
Finds first occurrence of a string within another
string mb_strstr ( string $haystack, string $needle [, bool $before_needle = false [, string $encoding = mb_internal_encoding() ]] )
mb_strstr() finds the first occurrence of needle in haystack and returns the portion of haystack. If needle is not found, it returns FALSE.
Parameters:
haystack
T