how to filter array with elements from another array with underscore?

Question

I have an jsonarray A but I would like to delete the elements which satisfy a certain condition. This condition is elements which have a certain id which are contained in another array called B. They both contain the same id property.

Suppose the arrays look like this:

A =[{"id":1},{"id":2},{"id":3}]
B =[{"id":1},{"id":2}]

So the function I am trying to create would result in:

result=[{"id":3}]

I tried this but not working:

result= _.each(A, function(gl) {
  return _.each(B, function(tg) {
    if (tg.id != gl.id) {
      return gl;
    }
  });
});

Miguel · Accepted Answer · 2015-04-03 08:00:23Z

2

Try using reject to filter out values you don't want:

var A =[{"id":1},{"id":2},{"id":3}];
var B =[{"id":1},{"id":2}];
            
var result = _.reject(A, function(item) {
   return _.find(B, {id: item.id});
});

alert(JSON.stringify(result)); // [{"id":3}]

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.js"></script>

Some underscore methods you can use to check if A is in B are find, findIndex, and where.

edited Apr 3, 2015 at 8:00

answered Apr 3, 2015 at 7:55

Miguel

20.7k5 gold badges47 silver badges68 bronze badges

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

Comments

huan feng · Accepted Answer · 2015-04-03 07:58:30Z

1

where is also fine:)

var A = _.reject(A, function(item) {
   return _.where(B, {id: item.id}).length > 0
});

answered Apr 3, 2015 at 7:58

huan feng

8,7043 gold badges40 silver badges66 bronze badges

Comments

NYTom · Accepted Answer · 2015-04-03 15:00:31Z

0

Easy using the open source project jinqJs

See Fiddle

var result = jinqJs().from(A).not().in(B, 'id').select();

answered Apr 3, 2015 at 15:00

NYTom

5242 silver badges14 bronze badges

1 Comment

Ivan Carosati Over a year ago

jinqJs link brings to a survey.

Collectives™ on Stack Overflow

how to filter array with elements from another array with underscore?

3 Answers 3

Comments

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related