How to remove undefined and null values from an object using lodash?

Question

I have a Javascript object like:

var my_object = { a:undefined, b:2, c:4, d:undefined };

How to remove all the undefined properties? False

Answer 1

I encountered a similar problem with removing undefined from an object (deeply), and found that if you are OK to convert your plain old object and use JSON, a quick and dirty helper function would look like this:

function stripUndefined(obj) {
  return JSON.parse(JSON.stringify(obj));
}

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description

"...If undefined, a function, or a symbol is encountered during conversion it is either omitted (when it is found in an object) or censored to null (when it is found in an array)."

Answer 2

For deep nested object you can use my snippet for lodash > 4

const removeObjectsWithNull = (obj) => {
    return _(obj)
      .pickBy(_.isObject) // get only objects
      .mapValues(removeObjectsWithNull) // call only for values as objects
      .assign(_.omitBy(obj, _.isObject)) // save back result that is not object
      .omitBy(_.isNil) // remove null and undefined from object
      .value(); // get value
};

Answer 3

According to lodash docs:

_.compact(_.map(array, fn))

Also you can filter out all nulls

Answer 4

The correct answer is:

_.omitBy({ a: null, b: 1, c: undefined, d: false }, _.isNil)

That results in:

{b: 1, d: false}

The alternative given here by other people:

_.pickBy({ a: null, b: 1, c: undefined, d: false }, _.identity);

Will remove also false values which is not desired here.

Answer 5

If you want to remove all falsey values then the most compact way is:

For Lodash 4.x and later:

_.pickBy({ a: null, b: 1, c: undefined }, _.identity);
>> Object {b: 1}

For legacy Lodash 3.x:

_.pick(obj, _.identity);

_.pick({ a: null, b: 1, c: undefined }, _.identity);
>> Object {b: 1}

Answer 6

You can simply chain _.omit() with _.isUndefined and _.isNull compositions, and get the result with lazy evaluation.

Demo

var result = _(my_object).omit(_.isUndefined).omit(_.isNull).value();

Update March 14, 2016:

As mentioned by dylants in the comment section, you should use the _.omitBy() function since it uses a predicate instead of a property. You should use this for lodash version 4.0.0 and above.

DEMO

var result = _(my_object).omitBy(_.isUndefined).omitBy(_.isNull).value();

Update June 1, 2016:

As commented by Max Truxa, lodash already provided an alternative _.isNil, which checks for both null and undefined:

var result = _.omitBy(my_object, _.isNil);