检索和使用json关联数组

Question

I use jquery and ajax to retrieve a dynamically made array made in php, like so:

$json = array();

while ($row = $stmt->fetch_assoc()) {

    $json['item_'.$row['id']] = $row['name'];
}

header('Content-type: application/json; charset=utf-8');
echo json_encode($json);
exit;

If I test the php file in browser, it outputs:

{"item_3":"Simon","item_1":"Miriam","item_2":"Shareen"}

So far so good. But how do I use that array in jquery?

I have this jquery ajax:

$.getJSON( "json.php", function(data) {
    console.log(data);
});

And testing that page in browser, it put this in console:

Object {item_3: "Simon", item_1: "Miriam", item_2: "Shareen"}

And that's ok right? Or should item_x also be in quotes?

Now, how do I USE that array in jquery?

If I try console.log(data[0]) it puts undefined

Answer 1

Try to use $.each() to iterate through that object,

$.each(data,function(key,val){
  console.log(key,val);
});

DEMO

If you want to access it without iterating it then simply use bracket notation

data['item_3'] //Simon

Or directly access it like,

data.item_3 //Simon

---

Then convert it like an array as per your wish like this,

var obj = {"item_3":"Simon","item_1":"Miriam","item_2":"Shareen"};

var convertedArray = $.map(obj,function(val,key){
    var obj = {}; obj[val] = key;
    return obj;
});

DEMO

Answer 2

As i mentioned in comments, php associative arrays become javascript objects, which cant be accessed numericaly.

A solution would be to send an array of objects instead:

while ($row = $stmt->fetch_assoc()) {

    $json[]= ['key'=>'item_'.$row['id'] , 'value' => $row['name']];
}

the in js:

data[0].key;
data[0].value;

EDIT obviously key is a misleading name in this example, better to call it something else:

$json[]= ['id'=>'item_'.$row['id'] , 'value' => $row['name']];
//js
data[0].id;