use a variable in JSON.stringify

Question

I use stringify in my node restful server to provide data:

answer = JSON.stringify({activities: result}, null, '\t');
return answer

where result is a js object; i receive the correct output for this:

{
"activities": [
    {
     "id": 1,
     "title": aaa
    },
    { 
     "id": 2,
     "title": bbb
    }
  ]
}

but now i would like to use a variable instead of a fixed string in the left part of stringify function; something like:

var name = "activities";
answer = JSON.stringify({name: result}, null, '\t');

this doesn't work, because name becomes a fixed string in the stringified object

SLaks · Accepted Answer · 2014-02-11 17:21:36Z

15

You need to build an object using indexer notation:

var name = ...;
var obj = {};
obj[name] = something;

answered Feb 11, 2014 at 17:21

SLaks

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2 Comments

With ES6, you can do it inside the object literal assignment, like { [name]: something }

write the answer in syntax of the question for the user readability.

Suhaib Janjua · Accepted Answer · 2017-08-03 08:27:22Z

6

If you want JSON.stringify() Object then try this:

var field = "my_field_name";

var obj = {};

obj[field] = value;

var myJSON = JSON.stringify(obj);

Suhaib Janjua

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answered Aug 3, 2017 at 8:07

Satish

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Paul · Accepted Answer · 2014-02-11 17:23:02Z

3

You can use new with an anonymous function to do it as well:

answer = JSON.stringify(new function(){ this[name] = result; }, null, '\t');

answered Feb 11, 2014 at 17:23

Paul

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