(PHP 5, PHP 7)
iconv_strrpos — Finds the last occurrence of a needle within a haystack
$haystack
   , string $needle
   [, string $charset = ini_get("iconv.internal_encoding")
  ] )
   Finds the last occurrence of a needle
   within a haystack.
  
   In contrast to strrpos(), the return value of
   iconv_strrpos() is the number of characters that
   appear before the needle, rather than the offset in bytes to the
   position where the needle has been found. The characters are counted
   on the basis of the specified character set charset.
  
haystackThe entire string.
needleThe searched substring.
charset
       If charset parameter is omitted,
       string are assumed to be encoded in
       iconv.internal_encoding.
      
   If haystack or needle is
   not a string, it is converted to a string and applied as the ordinal
   value of a character.
  
   Returns the numeric position of the last occurrence of
   needle in haystack.
  
   If needle is not found,
   iconv_strrpos() will return FALSE.
  
This function may
return Boolean FALSE, but may also return a non-Boolean value which
evaluates to FALSE. Please read the section on Booleans for more
information. Use the ===
operator for testing the return value of this
function.