how to sort multi dimensional array with object?

Question

Question: how to sort multi dimensional array with object?

Status : I've an array as following.

array(3) {
  [0]=>
  object(Photo_model)#25 (5) {
    ["id"]=>
    int(5)
    ["file_name"]=>
    string(36) "A49361605AE049D687CDC3FEAF7D3236.jpg"
    ["user_id"]=>
    int(1)
    ["challenge_id"]=>
    string(1) "2"
    ["score"]=>
    int(19)
  }
  [1]=>
  object(Photo_model)#28 (5) {
    ["id"]=>
    int(2)
    ["file_name"]=>
    string(36) "A49361605AE049D687CDC3FEAF7D3236.jpg"
    ["user_id"]=>
     int(1)
    ["challenge_id"]=>
    string(1) "2"
    ["score"]=>
    int(10)
  }
  [2]=>
  object(Photo_model)#29 (5) {
      ["id"]=>
      int(3)
      ["file_name"]=>
      string(36) "A49361605AE049D687CDC3FEAF7D3236.jpg"
      ["user_id"]=>
      int(1)
      ["challenge_id"]=>
      string(1) "2"
      ["score"]=>
      int(15)
  }
}

I tried to sort above array by score. I created a function as follow.

aarsort (&$array, 'score');
function aarsort (&$array, $key) {
    $sorter=array();
    $ret=array();
    reset($array);
    foreach ($array as $ii => $va) {
        $sorter[$ii]=$va[$key];
    }
    arsort($sorter);
    foreach ($sorter as $ii => $va) {
        $ret[$ii]=$array[$ii];
    }
    $array=$ret;
}

But it is not working. How can I sort the multidimensional array by key (score)?

result should be by id => 5,3,2

luiges90 · Answer 1 · 2012-12-01T15:13:42.677

3

Your array is only 1 dimensional, and there is an object in each array item.

After all, to sort a 1D array consisting of objects, and sort by a certain property of the objects, use usort

usort($array, function($a, $b) {
    return $a->score - $b->score
});

To get id => 5, 3, 2 from above, just loop through the array from the above code and access the property to get it

$ids = array();
foreach ($array as $item) {
    $ids[] = $item->id;
}
var_dump($ids);

And I am not sure if the order is right. If it turns out to be reverse order, just negate the result of the closure in the usort function.

edited Dec 01 '12 at 15:13

answered Dec 01 '12 at 09:21

luiges90

4,493
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I want to sort the arrary by score column. how can I? – Thu Ra Dec 01 '12 at 10:51
`score` is a property of your objects according to your `var_dump` of your array... – luiges90 Dec 01 '12 at 15:18

score 0 · Answer 2 · answered Dec 01 '12 at 09:33

It just example.

//$newarray for store all array id
//$array is your previous array . You just enter your all index whose key id store in new array 
$newarray = array();
foreach($array as $obj => $id)
{
    $newarray[] = $id[$key];
}

array_multisort($newarray,SORT_ASC,$array);

score 0 · Answer 3 · answered Dec 01 '12 at 12:45

I've done this problem by php.net

// Obtain a list of columns
                foreach ($array as $key => $row) {
                    $_score[$key]  = $row->score;
                }

                // Sort the data with volume descending, edition ascending
                // Add $data as the last parameter, to sort by the common key
                array_multisort($_score, SORT_DESC, $array);

how to sort multi dimensional array with object?

3 Answers3