星期六到星期五的星期几组的日期组的PHP数组

Question

I've an array containing items. Each item has a title and startdate. Now i want to group these items by week. If i look at the documentation, the format->('W') weeks starts on monday. I need to change this to saturday.

        $items = [
        [   // friday
            'title'     => 'test',
            'startdate' => '2016-03-18',    // first group
        ],
        [   // saturday
            'title'     => 'test',
            'startdate' => '2016-03-19', // second group
        ],
        [   // sunday
            'title'     => 'test',
            'startdate' => '2016-03-20', // second group
        ],
        [   // monday
            'title'     => 'test',
            'startdate' => '2016-03-21', // second group
        ],
        [   // saterday
            'title'     => 'test',
            'startdate' => '2016-03-26', // third group
        ],
    ];

I've something like this but its not working correctly

        foreach($items as $item) {
            // group by week
            $startDate      =  \DateTime::createFromFormat('Y-m-d', $item['startdate']);
            $currectWeek    = $startDate->format('W');
            $saturday       = 6;
            $friday         = 5;

            $test = clone $startDate;

            if($currectWeek !== 5){
                $test->modify('last friday');
            }

            if($currectWeek !== 6){
                $test->modify('next saturday');
            }

            $a = $test->format('W');

            if(!isset($items_by_week[$a])){
                $items_by_week[$a] = [];
            }

            $items_by_week[$a][] = [
                'title'    => $item['title'],
                'date'     => $item['startdate'],
            ];
        }

Answer 1

Try the following code

$startDate = \DateTime::createFromFormat('Y-m-d', $item['startdate']);
$week = intval($startDate->format('W'));
$day = intval($startDate->format('N'));

$a = ($day < 6 ) ? $week-1 : $week;