如何以不同的顺序对数组进行排序

Question

I have an array which looks like this.

Array
(

[0] => Array
    (
        [cartId] => 667
        [isPack] => 1
    )

[1] => Array
    (
        [cartId] => 668
        [isPack] => 1
    )

[2] => Array
    (
        [cartId] => 672
        [isPack] => 2
    )

[3] => Array
    (
        [cartId] => 673
        [isPack] => 2
    )

)

I want to make an array by isPack element,which should look something like this.

Array (

[1] => Array
    (

       [0] => Array
            (
                [cartId] => 667
            )

        [1] => Array
            (
                [cartId] => 668
            )

    )
  [2] => Array
    (
        [0] => Array
            (
                [cartId] => 672
            )

        [1] => Array
            (
                [cartId] => 673
            )
    )  
 )

Array two will be two array in which isPack will be array key,and other information will belong to its subarray.

How can I do this? thanks in advance :)

Answer 1

  $new=array();
     $arr = array( array('cartId' => 667,'isPack' => 1),array('cartId' => 668,'isPack' => 1),array('cartId' => 672,'isPack' => 2),array('cartId' => 673,'isPack' => 2));
     for($i=0;$i<count($arr);$i++) {
          $l = $arr[$i]['isPack'];
     $new[$l][]['catid']= $arr[$i]['cartId'];
     }
     print_r($new);

and output:-

Array
(
    [1] => Array
        (
            [0] => Array
                (
                    [catid] => 667
                )

            [1] => Array
                (
                    [catid] => 668
                )

        )

    [2] => Array
        (
            [0] => Array
                (
                    [catid] => 672
                )

            [1] => Array
                (
                    [catid] => 673
                )

        )

)