PHP date format and date calculation and get the current week, month and tail date

PHP date formatting and date calculation and when getting before week, month and end date

PHP date format Sample code:

/ **
     * Formatting time
     * $ type: type
     * $ strDate: time string to be processed
     *
     * Year Y: four-digit year y: two-digit year
     * Month m: two-digit month n: one-digit month M: English month
     * Date d: Two-digit date j: One-digit date D: English date
     * Hour: H, minute: i, second: s
     ** /
    public function GetFormatDate ($ type = 1, $ strDate = '') {
            $ time = time ();
            if (isset ($ strDate) &&! empty ($ strDate)) {
                $ time = strtotime ($ strDate);
            }

            switch ($ type) {
                case 1:
                   return date ("H: i", $ time);
                case 2:
                    return date ("m month d H: i", $ time);
                case 3:
                    return date ("m / d H: i", $ time);
                case 4:
                    return date ("Y: m, d, H: i", $ time);
                case 5:
                    return date ("Y / m / d H: i", $ time);
                case 6:
                    return date ("H: i: s", $ time)
                case 7:
                    return date ("Y-m-d H: i: s", $ time);
                case 8:
                    return date ("Y / m / d H: i: s", $ time);
                default:
                    return $ strDate;
            }
    } 

Date Calculation Sample code:

   /** *
     time plus minus processing
     * $strDate: Time string to be processed
     * $days:   Add and Subtract days
     **/public
    function ChangeDate ($strDate, $ Days) {
          $time = time ();
          if (Isset ($strDate) &&!empty ($strDate)) {
              $time = Strtotime ($strDate);
          }

         Return date (' y-m-d h:i:s ', Strtotime ("$days Day", $time));
    }

Get the current week, the month-and-tail date sample code:

/ **
     * Get the beginning and end of the current week and month
     *
     * $ dateArr ['W1']: Monday
     * $ dateArr ['W7']: Weekend
     * $ dateArr ['M1']: month head
     * $ dateArr ['M2']: end of the month
     ** /
    public function GetCurrentDateInfo () {
       $ dayTimes = 24 * 60 * 60;
       $ dateArr = []; $ temp = '';

       $ weekIndex = (int) date ('w');
       switch ($ weekIndex) {
            case 0:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('+ 1 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 7 day'));
                break;
            case 1:
                $ dateArr ['W1'] = date ('Y-m-d 00:00:00');
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 6 day'));
                break;
            case 2:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('-1 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 5 day'));
                break;
            case 3:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('-2 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 4 day'));
                break;
            case 4:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('-3 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 3 day'));
                break;
            case 5:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('-4 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 2 day'));
                break;
            case 6:
                $ dateArr ['W1'] = date ('Y-m-d 00: 00: 00', strtotime ('-5 day'));
                $ dateArr ['W7'] = date ('Y-m-d 23: 59: 59', strtotime ('+ 1 day'));
                break;
        }


       // 1-12: January to December
       $ monthIndex = (int) date ('m');
       switch ($ monthIndex) {
           case 1:
               $ temp = date ('Y-02-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 2:
               $ temp = date ('Y-03-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 3:
               $ temp = date ('Y-04-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 4:
               $ temp = date ('Y-05-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 5:
               $ temp = date ('Y-06-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 6:
               $ temp = date ('Y-07-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 7:
               $ temp = date ('Y-08-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 8:
               $ temp = date ('Y-09-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 9:
               $ temp = date ('Y-10-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 10:
               $ temp = date ('Y-11-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 11:
               $ temp = date ('Y-12-01 00:00:00');
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
           case 12:
               $ temp = date ((date ('Y') + 1). "-01-01 00:00:00");
               $ dateArr ['M1'] = date ('Y-m-01 00:00:00');
               $ dateArr ['M2'] = date ('Y-m-d 23: 59: 59', strtotime ($ temp)-$ dayTimes);
               break;
       }


       return $ dateArr;
    }

The above code is for reference only, the place of omission also please point out to improve!