if( !function_exists('mb_str_split')){
function mb_str_split( $string = '', $length = 1 , $encoding = null ){
if(!empty($string)){
$split = array();
$mb_strlen = mb_strlen($string,$encoding);
for($pi = 0; $pi < $mb_strlen; $pi += $length){
$substr = mb_substr($string, $pi,$length,$encoding);
if( !empty($substr)){
$split[] = $substr;
}
}
}
return $split;
}
}