Add element into JSON Object using JavaScript

Question

I have an JSON Object such as:

{result: 
   [ 
     { 
       "id": "1",
       "name": "name 1"
      },
      { 
       "id": "2",
       "name": "name 2"
      },
      { 
       "id": "3",
       "name": "name 3"
      }
  ]
}

I am wondering how can I add element (for example: "user":"username") into each object in this this JSON such as the result will come out:

{result: 
   [ 
     { 
       "id": "1",
       "name": "name 1",
       "user": "user 1"
      },
      { 
       "id": "2",
       "name": "name 2",
       "user": "user 2"
      },
      { 
       "id": "3",
       "name": "name 3",
       "user": "user 3"
      }
  ]
}

I was trying to do something like:

result.user = user.data

But it doesnt come out what I need. I am wondering if I can use a for loop such as

for (var i = 0; i < result.length; i++) {
  result.user = user.data;
}

If you're modifying it in this way, it isn't JSON. JSON is a *textual notation* for data exchange. [(More.)](http://stackoverflow.com/a/2904181/157247) If you're dealing with JavaScript source code, and not dealing with a *string*, you're not dealing with JSON. — T.J. Crowder, Dec 05 '16 at 18:47

rfornal · Answer 1 · 2016-12-05T18:48:31.510

3

You're close ...

for (var i = 0; i < result.length; i++) {
  // result.user = user.data;
  result[i].user = "user " + (i + 1);
}

Essentially, result is an array of objects; you need to tell it which one to reference when accessing the internals.

edited Dec 05 '16 at 18:48

answered Dec 05 '16 at 18:46

rfornal

5,072
5
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Adjusted and commented out what was not needed. Thanks – rfornal Dec 05 '16 at 18:48

Mahi · Answer 2 · 2016-12-05T18:48:26.437

1

yes use index of array . since you want 1 for 0th element so add 1 to index. forEach will iterate over each array element . where a is the element and index is ath element index.

var json={result: [ { "id": "1", "name": "name 1" }, { "id": "2", "name": "name 2" }, { "id": "3", "name": "name 3" } ] };
json["result"].forEach(function(a,index){
  a["user"]="user"+(index+1);
})
console.log(json);

edited Dec 05 '16 at 18:48

answered Dec 05 '16 at 18:47

Mahi

1,707
11
22

Again: Code dumps are not *useful* answers. – T.J. Crowder Dec 05 '16 at 18:48
just another hint, please use a different variable name if the content is not really a [JSON](http://json.org/) string. it looks like an object. – Nina Scholz Dec 06 '16 at 10:09
@NinaScholz isn't it json ? – Mahi Dec 06 '16 at 10:19
**json is always a string**, not an object. it it not even a synonym for it. – Nina Scholz Dec 06 '16 at 10:23
@NinaScholz no i am serious. tell me na please. – Mahi Dec 06 '16 at 10:29
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/129892/discussion-between-nina-scholz-and-mahi). – Nina Scholz Dec 06 '16 at 10:29

score 0 · Answer 3 · answered Dec 05 '16 at 18:52

First you need to put this json in a variable, then you can interate the object acessing the result array.

var object = {result: 
       [ 
         { 
           "id": "1",
           "name": "name 1",
           "user": "user 1"
          },
          { 
           "id": "2",
           "name": "name 2",
           "user": "user 2"
          },
          { 
           "id": "3",
           "name": "name 3",
           "user": "user 3"
          }
      ]
    };


for (var i = 0; i < object.result.length; i++) {
  object.result[i].user = "user " + i;
}

console.log(object);

Add element into JSON Object using JavaScript

3 Answers3