从PHP周中获得每周的一周

I have a variable $yearweek and I would get the day of the week: ex:

$yearweek = 201630
$monday   = '2016-07-25'
$thuesday = '2016-07-26'
...

    # Create new DateTime object
    $date = new DateTime();

    # Get Week start date (monday)
    $arr['monday']  = $date->setISODate(2016, 30)->format('d-m-Y');

    # For example this is sunday, you can do this for all days by changing +6
    $arr['sunday']  = $date->modify('+6 days')->format('d-m-Y');