get date diff exclude multiple day

getdatediff.php

use Carbon\Carbon;
    $dt = Carbon::create(2018, 9, 17);
    $dt2 = Carbon::create(2018, 9, 24);
    $holiday = ['2018-09-21'];
    $offday = ['2018-09-22', '2018-09-21'];
    $daysForExtraCoding = $dt->diffInDaysFiltered(function(Carbon $date) use ($holiday, $offday){
        return !in_array($date->toDateString(), $offday) && !in_array($date->toDateString(), $holiday);
    }, $dt2);

    dd($daysForExtraCoding);
    return $daysForExtraCoding;