Simple object manipuation of javascript

Question

function abc(req, res, next) {
  let imageName = req.body.name;
   const obj = {
    imageName: {
      status: true,
      url: "abc"
    }
 }

In above function I have a varaible declared 'imageName'. I just need to use result that is got at 'imageName' variable at 'obj'. suppose I get 'alpha' from req.body.name then I want to use that in 'obj' like obj = {aplha: {status: true, url: "abc"} }.

You can do `let obj = {}` and `obj[req.body.name] = { status: true, url: "abc" }` — kgangadhar, Feb 12 '18 at 17:55
Possible duplicate of [Using a variable for a key in a JavaScript object literal](https://stackoverflow.com/questions/2274242/using-a-variable-for-a-key-in-a-javascript-object-literal) — , Feb 12 '18 at 17:57

score 1 · Answer 1 · answered Feb 12 '18 at 17:55

You can use bracket notation to provide a dynamic key to an object.

let imageName = 'alpha';
const obj = {
  [imageName]: {
    status: true,
    url: "abc"
  }
}
console.log(obj);

Your code will be

function abc(req, res, next) {
  let imageName = req.body.name;
   const obj = {
    [imageName]: {
      status: true,
      url: "abc"
    }
 }

talemyn · Answer 2 · 2018-02-12T18:32:21.723

If I'm reading your question right, you need to use the bracket notation with the object to get a dynamic key value:

function abc(req, res, next) {
    const obj = {};
    obj[req.body.name] = {status: true, url: "abc"};
}

UPDATE

On a side note, you can still reference the value later using the dot notation later on . . . for example, if you want to later check to see if "obj" has an "alpha" value, you can do it with either if (obj.alpha . . . or if {obj[alpha] . . .), but only the bracket notation approach will work when using a dynamic, variable-based key (e.g., if (obj[req.body.name] . . .)).

score 0 · Answer 3 · answered Feb 12 '18 at 17:56

0

If I understand the question right you want to update the obj object? do like so

obj['newKey'] = { status: true, url: "abc" }

answered Feb 12 '18 at 17:56

digital-pollution

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score 0 · Answer 4 · answered Feb 12 '18 at 17:59

While I cannot find the appropriate use case for this, you could always store the value in req.body.name and use that as a key in your obj like so:

function abc(req, res, next) {
   let imageName = req.body.name;
   const obj = {}
   obj[imageName] = {
      status: true,
      url: "abc"
    }
 }

Simple object manipuation of javascript

4 Answers4