how to sort multi dimensional array with object? [duplicate] - php

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How do I sort a multidimensional array by one of the fields of the inner array in PHP? [duplicate]
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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

Answer 1

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.

Answer 2

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);

Answer 3

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);