Get position with variable and then modify specific object in mongodb

Question

How can I make this query use my variable instead of the hard coded 0?

let pos = 0;

{$set: {'answers.0.acknowledged': data}}

Akrion · Accepted Answer · 2019-05-29 16:31:40Z

2

Usually you choices are template literals, Array.join, String.concat etc:

let pos = 0;
let data = 'data';

let query = {$set: {[['answers.', pos,'.acknowledged'].join('')]: data}}

console.log(query);

With String.concat:

let pos = 0;
let data = 'data';
let query = {$set: {['answers.'.concat(pos,'.acknowledged')]: data}}
console.log(query);

Array.join, String.concat has a much better browsers support where template literals do not. If they were to be used @ the client side. In your case if you are using them at the back end you probably have nothing to worry about.

edited May 29, 2019 at 16:31

answered May 29, 2019 at 16:26

Akrion

18.6k1 gold badge38 silver badges58 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

mickl · Accepted Answer · 2019-05-29 16:11:07Z

2

You can use ES6 String Interpolation and Computed Property Names to build the key for $set:

let pos = 0;
let data = 'some data';
let q = {$set: {[`answers.${pos}.acknowledged`]: data}}
console.log(q);

edited May 29, 2019 at 16:11

answered May 29, 2019 at 15:59

mickl

50.1k9 gold badges71 silver badges99 bronze badges

Collectives™ on Stack Overflow

Get position with variable and then modify specific object in mongodb

2 Answers 2

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related