将数组推入JSON但得到了不需要的结果

Question

I suck at formatting, maybe I had a bad foundation. I have a json like this

'first_name'=>'steve', 'msg'=>'something here','profile_id'=>1

and I want to push a new item into it, I wrote

$i = array('first_name'=>'steve', 'msg'=>'something here','profile_id'=>1);
$loginId = array($_GET['login_id']);
array_push($i,$loginId);

echo json_encode($i);

The result I got is strange:

Answer 1

$i = array('first_name'=>'steve', 'msg'=>'something here','profile_id'=>1);
$loginId = $_GET['login_id'];

$i['login_id']=$loginId;    
echo json_encode($i);

The reason array_push didn't work is because you are treating $i as an array (collection) of objects (arrays), while it is just a key-value list (map).

If the array is like K1=>V1, K2=>V2, use $arr[K3]=V3 to add another pair.

If the array is like [(k1,v1), (k2,v2)], then array_push($arr,(k3,v3));