Convert javascript object keys to real int after JSON encoded

Question

I have this:

var a = {};
a[1] = 1;
a[4] = 4;
console.log(JSON.stringify(a));

then I get:

{"1":1,"4":4}

but I want to get:

{1:1,4:4}

how to reach this? In other words, I want to keys be real int.

If it's useful, you can declare `a` as an array (`[]`) and get back `[null,1,null,null,4]` after *JSONification* - which when parsed pack will give the expected values at those *indices*. — techfoobar, Jun 27 '16 at 22:10
What is the purpose of why you need that format? Do you want to send to the server that way, are you trying reference them a specific way later? — KevBot, Jun 27 '16 at 22:20
right, solution is here:http://stackoverflow.com/questions/3445953/how-can-i-force-php-to-use-strings-for-array-keys — John Smith, Jun 27 '16 at 22:24

Artem Arkhipov · Accepted Answer · 2016-06-27T22:41:11.927

When you call JSON.stringify() method it creates a valid JSON string. One of the rules for valid JSON is that every property should be in "quotes".

So thats why it is impossible to get such result as you want using JSON.stringify.

If you want to just convert such object to array it is possible, for example usin such function.

function numerableObjectToArr(obj) {
  var result = [];
  var keys = Object.keys(obj);
  keys.forEach(function(item){
    result.push(obj[item]);
  })
  return result; 
}

var a = {};
a[1] = 1;
a[4] = 4;
numerableObjectToArr(a); // returns [1, 4]

But in this way you will just receive Array with values of existing properties in the obj.

But if your prop name means the index in the array, and you are sure that there will be always number as a prop name - you can improve this function:

function numerableObjectToArr(obj) {
  var result = [];
  var keys = Object.keys(obj);
  keys.forEach(function(item){
    result[+item] = obj[item];  //we put index, then we put value to that place in array
  })
  return result; 
}

var a = {};
a[1] = 1;
a[4] = 4;
numerableObjectToArr(a);  // returns [undefined, 1, undefined, undefined, 4]

yea, I see, I realized that its a server-side issue: http://stackoverflow.com/questions/3445953/how-can-i-force-php-to-use-strings-for-array-keys — John Smith, Jun 28 '16 at 08:01

k..a..b · Answer 2 · 2016-07-06T02:29:26.807

1

I'm not sure you can do what you're trying to do the as the keys have to be string values. I'd advise having string name for your keys (i.e 1 = One, 2 = Two, etc). You could then try this:

 var a = {};
    a.one = 1;
    a.two = 2;
    a.three = 3;
    a.four = 4;

    console.log(JSON.stringify(a));

I hope this helps.

edited Jul 06 '16 at 02:29

answered Jun 27 '16 at 22:50

k..a..b

61
1
12

score -1 · Answer 3 · answered Jun 27 '16 at 22:27

-1

var a = {};
a[1] = 1;
a[4] = 4;
alert(JSON.stringify(a).replace(/\"([0-9]+)\":/g, '$1:'));

But it is kludge. JSON - has a string keys.

answered Jun 27 '16 at 22:27

Alexander Goncharov

1,572
17
20

2

You can't parse JSON with regex. – Oriol Jun 27 '16 at 22:33
1

it is not parsing. It is converting. – Alexander Goncharov Jun 27 '16 at 22:52
2

Yes, that's the point. To do it properly, you need to parse it, and then use a custom stringifier. You don't want [Zalgo to come](http://stackoverflow.com/a/1732454/1529630), do you? – Oriol Jun 27 '16 at 22:54
1

I dont see any troubles to use regexps for replacing in JSON. But replacings in JSON - it is bad by itself. – Alexander Goncharov Jun 27 '16 at 23:53
I value this help, though Im not keen for raping JSON either. – John Smith Jun 28 '16 at 08:01

Convert javascript object keys to real int after JSON encoded

3 Answers3