Check javascript array of objects property

Question

I have the following javascript array of objects ,I need to check output property if at least one object is true return true else return false,Can anyone help me to implement that?

var array=[{"id":100,"output":false},{"id":100,"output":false},
{"id":100,"output":true}]

Possible duplicate of [How to loop through an array containing objects and access their properties](http://stackoverflow.com/questions/16626735/how-to-loop-through-an-array-containing-objects-and-access-their-properties) — Turnip, Oct 11 '16 at 11:45
use [Array.prototype.some](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/some) should stop the iteration once one value is found and return a Boolean — Endless, Oct 11 '16 at 11:45

Nina Scholz · Accepted Answer · 2016-10-11T11:47:00.423

11

You could use Array#some

The some() method tests whether some element in the array passes the test implemented by the provided function.

var array = [{ "id": 100, "output": false }, { "id": 100, "output": false }, { "id": 100, "output": true }];
    result = array.some(function (a) { return a.output; });

console.log(result);

edited Oct 11 '16 at 11:47

answered Oct 11 '16 at 11:46

Nina Scholz

376,160
25
347
392

score 1 · Answer 2 · answered Oct 11 '16 at 11:48

1

function hasOneTrue(a){
  return !!a.filter(function(v){
    return v.output;
  }).length;
}

var array = [{"id":100,"output":false}, {"id":100,"output":false}, {"id":100,"output":true}]
console.log(hasOneTrue(array)); // true

answered Oct 11 '16 at 11:48

Robiseb

1,576
2
14
17

you filter all array objects even if `true` in first. better use `some()` – Maxx Oct 11 '16 at 11:51
@Maxx I agree :) – Robiseb Oct 11 '16 at 11:52

score 0 · Answer 3 · answered Oct 11 '16 at 11:50

You could Loop over the array and check every property.

var array = [
    {"id":100,"output":false},
    {"id":100,"output":false},
    {"id":100,"output":true}
];

function testOutput ( array ) {
    for (el in array)
        if ( el.output ) return true;

    return false;
}

testOutput (array);

Best Regards

score 0 · Answer 4 · answered Oct 11 '16 at 11:59

fastest + most compatible

var result = false
var json = [{"id":100,"output":false},{"id":100,"output":false},{"id":100,"output":true}]

for(
  var i = json.length;
  !result && i;
  result = json[--i].output
);

console.log("at least one? ", result)

Check javascript array of objects property

4 Answers4