将数组中的类似值分组

Question

Here is the array, which I have posted through Ajax and get into the ajax.php file. Now i want to add a new array, as shown below.

Array
(
    [0] => Array
        (
            [contact_id] => 5000
            [invoice] => 476
        )

    [1] => Array
        (
            [contact_id] => 5000
            [invoice] => 396
        )

    [2] => Array
        (
            [contact_id] => 1490
            [invoice] => 1083
        )

    [3] => Array
        (
            [contact_id] => 1490
            [invoice] => 498


  )
)

I also want to add this if contact id are same, then invoice will be added

Array
(
    [0] => Array
        (
            [contact_id] => 5000
            [invoice] => Array (
                    [0] =>476,
                    [1] =>396
            )
        )

    [2] => Array
        (
            [contact_id] => 1490
            [invoice] => Array (
                    [0] =>1083,
                    [1] =>498
            )
        )
)

I tried to do it, without success. Here is my code:

$invtemp =array();
 foreach($_POST['invoice_id'] as $value){
    if(!in_array($value['contact_id'], $invtemp, true)){
         $arr = array($value['contact_id'] => $value['invoice'] );
         array_push($invtemp, $arr);    
    }
}

Answer 1

I think you can achieve with simple foreach:

foreach ($array as $value) {
    $arr[$value['contact_id']]['contact_id'] = $value['contact_id'];
    $arr[$value['contact_id']]['invoice'][] = $value['invoice'];
}

print_r($arr);

This provides:

Array
(
    [5000] => Array
        (
            [contact_id] => 5000
            [invoice] => Array
                (
                    [0] => 476
                    [1] => 396
                )

        )

    [1490] => Array
        (
            [contact_id] => 1490
            [invoice] => Array
                (
                    [0] => 1083
                    [1] => 498
                )

        )

)

To reset the keys:

print_r(array_values($arr));

---

Not so important, but to make it cleaner, you can use extract:

foreach ($array as $value) {
    extract($value);
    $arr[$contact_id]['contact_id'] = $contact_id;
    $arr[$contact_id]['invoice'][] = $invoice;
}

print_r($arr);