Javascript - One-liner to extract values from object to array

Question

I quite simple one:

I have a Javascript object with some properties whose values are arrays, with the following structure:

let obj = {emails: ["[email protected]", "[email protected]"], nickname: ["asdf"],...}

I need to get an array of arrays with only the values, like the following:

let obj2 = [["[email protected]"], ["[email protected]"], ["asdf"],...]

With Object.values(obj), I get [["[email protected]", "[email protected]"], ["asdf"],...], which is not exactly what I am looking for, but it is a good starting point...

Also, I am looking for a one-liner to do it, if possible. Any ideas? Thanks.

Answer 1

An alternative using the function reduce.

This approach adds objects and arrays from the first level.

As you can see, this approach evaluates the type of the object.

let obj = {emails: ["[email protected]", "[email protected]"], nickname: ["asdf"]}

var result = Object.values(obj).reduce((a, c) => {
  if (Array.isArray(c)) return a.concat(Array.from(c, (r) => [r]));
  return a.concat([c]);
}, []);

console.log(result);

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One line approach (excluding the checking for array type):

let obj = {emails: ["[email protected]", "[email protected]"], nickname: ["asdf"]},
    result = Object.values(obj).reduce((a, c) => (a.concat(Array.from(c, (r) => [r]))), []);

console.log(result);

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Answer 2

You can use Object.values to get array of values and then concat and spread syntax ... to get flat array and then map method.

let obj = {emails: ["[email protected]", "[email protected]"], nickname: ["asdf"]}
const values = [].concat(...Object.values(obj)).map(e => [e])
console.log(values)