PHP array_unique is converted to object

Question

Here is a dummy example:

$errors = [];
for ($i = 0; $i < 3; $i++) {
    $errors[] = [
        'id' => $i
    ];
}

$errors[] = [
    'id' => 0
];

for ($i = 3; $i < 5; $i++) {
    $errors[] = [
        'id' => $i
    ];
}


var_dump($errors);
echo "<br/>";
var_dump(array_unique($errors, SORT_REGULAR));

The output above is:

array(6) { 
    [0]=> array(1) { ["id"]=> int(0) } 
    [1]=> array(1) { ["id"]=> int(1) } 
    [2]=> array(1) { ["id"]=> int(2) } 
    [3]=> array(1) { ["id"]=> int(0) } 
    [4]=> array(1) { ["id"]=> int(3) } 
    [5]=> array(1) { ["id"]=> int(4) } 
} 

array(5) { 
    [0]=> array(1) { ["id"]=> int(0) } 
    [1]=> array(1) { ["id"]=> int(1) } 
    [2]=> array(1) { ["id"]=> int(2) } 
    [4]=> array(1) { ["id"]=> int(3) } 
    [5]=> array(1) { ["id"]=> int(4) } 
}

As you can see, the second case, the index 3 is missing. So when I return this through an API, it is returned as an object with keys, 0,1,2,4,5.

array_unique() does not convert your array into an object. — Xorifelse
– Xorifelse, Commented Mar 13, 2017 at 22:34
it doesn't convert it into an object, it turns it into an associated array — Brian McCall
– Brian McCall, Commented Mar 13, 2017 at 22:34
Okay, but I then return this item through an API interface, and Javascript receives it as an object. — Kousha
– Kousha, Commented Mar 13, 2017 at 22:36
Are you doing anything like json_encode() when you return the array? — Mark Baker
– Mark Baker, Commented Mar 13, 2017 at 22:37

Xorifelse · Accepted Answer · 2017-03-13 23:15:42Z

2

The function array_unique() filters out equal values so the reason why #3 of the index is missing is because its equal to #0.

You can re-index the array with array_values():

var_dump(array_values(array_unique($errors, SORT_REGULAR)));

JavaScript perceives PHP's associative array's as an object because it only understands numeric keyed arrays.

You should be using json to communicate between both languages:

echo json_encode($errors);

As this would cause in javascript the outer the value to be turned into an array and turn each item into an object.

var arr = JSON.parse(outputofjson_encode);

console.log(arr[0].id);

edited Mar 13, 2017 at 23:15

answered Mar 13, 2017 at 23:05

Xorifelse

7,9411 gold badge29 silver badges38 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Kousha · Accepted Answer · 2017-03-13 23:32:27Z

0

I ended up using array_values:

$errors = [];
for ($i = 0; $i < 3; $i++) {
    $errors[] = [
        'id' => $i
    ];
}

$errors[] = [
    'id' => 0
];

for ($i = 3; $i < 5; $i++) {
    $errors[] = [
        'id' => $i
    ];
}

$errors = array_values(array_unique($errors, SORT_REGULAR));

answered Mar 13, 2017 at 23:32

Kousha

36.7k59 gold badges191 silver badges318 bronze badges

1 Comment

Kousha Over a year ago

Cause I did not see your response! I marked yours as a the solution

Collectives™ on Stack Overflow

PHP array_unique is converted to object

2 Answers 2

Comments

1 Comment

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Related