I am trying to find out in lodash javascript library, how to find out filter array of objects multiple values of key. something similar to SQL - WHERE KEY in (val1, val2)

Having said, with following example :

var users = [
   { 'user': 'barney', 'age': 36, 'active': true },
   { 'user': 'fred',   'age': 40, 'active': false },
   { 'user': 'Avding',   'age': 34, 'active': true }
];

_.filter(...)

How can I find users, who's age in (34, 36) ?? numbers can also change runtime

I am trying to find out in lodash javascript library, how to find out filter array of objects multiple values of key. something similar to SQL - WHERE KEY in (val1, val2)

Having said, with following example :

var users = [
   { 'user': 'barney', 'age': 36, 'active': true },
   { 'user': 'fred',   'age': 40, 'active': false },
   { 'user': 'Avding',   'age': 34, 'active': true }
];

_.filter(...)

How can I find users, who's age in (34, 36) ?? numbers can also change runtime

• javascript
• filter
• lodash

5 Answers 5

Lodash's filter accepts a predicate. You can create the predicate using partial application, so you can change the values easily:

var users = [
   { 'user': 'barney', 'age': 36, 'active': true },
   { 'user': 'fred',   'age': 40, 'active': false },
   { 'user': 'Avding',   'age': 34, 'active': true }
];

var predicate = function(start, end) {
  return function(user) {
    return _.inRange(user.age, start, end + 1);
  }
}

var result = _.filter(users, predicate(34, 36));

console.log('inRange', result);

/** is equal predicate **/

var predicate = function() {
  var args = _.toArray(arguments);
  
  return function(user) {
    var equalToUserAge = _.partial(_.isEqual, user.age);
    
    return args.some(equalToUserAge);
  }
}

var result = _.filter(users, predicate(34, 40));

console.log('equals', result);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.16.4/lodash.min.js"></script>

You can also do this easily with vanilla JS as well (the example uses ES6):

var users = [
   { 'user': 'barney', 'age': 36, 'active': true },
   { 'user': 'fred',   'age': 40, 'active': false },
   { 'user': 'Avding',   'age': 34, 'active': true }
];

const predicate1 = (start, end) => ({ age }) =>
  age >= start && age <= end;

const result1 = users.filter(predicate1(34, 36));

console.log('in range', result1);

const predicate2 = (...args) => ({ age }) =>
  args.some((num) => age === num);

const result2 = users.filter(predicate2(34, 40));

console.log('is equal', result2);

const users = [
  { 'user': 'barney', 'age': 36, 'active': true },
  { 'user': 'fred',   'age': 40, 'active': false },
  { 'user': 'Avding',   'age': 34, 'active': true }
];

const minAge = 34;
const maxAge = 36;

const filtered = _.filter(users, (user) => {
  return user.age >= minAge && user.age <= maxAge;
});

This is old but I had the same issue. I don't know if it is efficient but the below function returns what I am looking for. I had to flatten the result to keep the same format as the input.

var users = [
    { 'user': 'barney', 'age': 36, 'active': true },
    { 'user': 'fred',   'age': 40, 'active': false },
    { 'user': 'Avding',   'age': 34, 'active': true }
];

var ages = [{"age": 36},{"age": 34}]

function filterAges(array, vals) {
    var result=[];
    for (i = 0; i < vals.length; i++) {
        result.push(_.filter( array, vals[i] ));
    }
    return _.flattenDepth(result, 1);
}

var users = [
  { user: 'barney', age: 36, active: true },
  { user: 'fred',  age: 40, active: false },
  { user: 'travis', age: 34, active: true}
];
var result = []
var x = _.filter(users, function(o) {
  _.map([36,34], function(p) {
    if (o.age == p) {
      result.push(o);
    }
  });
});
console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>

You can do something like this:

_.filter( object, { 'age': '34', 'age': '24' } );

The issue is if you are making this dynamically you can not have the same key in an object more than once.