How to omit specific properties from an object in JavaScript

Question

Is there a clean way to return a new object that omits certain properties that the original object contains without having to use something like lodash?

Answer 1

If you already use lodash, you may also do omit(obj, ["properties", "to", "omit"]) to get a new Object without the properties provided in the array.

Answer 2

Omit and array of keys, using ES7 w/ recursion.

function omit(keys, obj) {
  if (!keys.length) return obj
  const { [keys.pop()]: omitted, ...rest } = obj;
  return omit(keys, rest);
}

This builds on top of @Eddie Cooro answer.

Answer 3

One solution, I'm sure many others exist.

const testObj = {
    prop1: 'value1',
    prop2: 'value2',
    prop3: 'value3'
};

const removeProps = (...propsToFilter) => obj => {
   return Object.keys(obj)
   .filter(key => !propsToFilter.includes(key))
   .reduce((newObj, key) => {
       newObj[key] = obj[key];
       return newObj;
   }, {});
};


console.log(removeProps('prop3')(testObj));
console.log(removeProps('prop1', 'prop2')(testObj));

Edit: I always forget about delete...

const testObj = {
    prop1: 'value1',
    prop2: 'value2',
    prop3: 'value3'
};

const removeProps = (...propsToFilter) => obj => {
   const newObj = Object.assign({}, obj);
   propsToFilter.forEach(key => delete newObj[key]);
   return newObj;
};


console.log(removeProps('prop3')(testObj));
console.log(removeProps('prop1', 'prop2')(testObj));

Answer 4

If you know the list of the properties that you want preserved as well as omitted, the following "whitelisting" approach should work:

const exampleFilter = ({ keepMe, keepMeToo }) => ({ keepMe, keepMeToo })

console.log(
  exampleFilter({
    keepMe: 'keepMe',
    keepMeToo: 'keepMeToo',
    omitMe: 'omitMe',
    omitMeToo: 'omitMeToo'
  })
)

Answer 5

Sure, why not something like:

var original = {
  name: 'Rory',
  state: 'Bored',
  age: '27'
};

var copied = Object.assign({}, original);
delete copied.age;

console.log(copied);

https://jsfiddle.net/4nL08zk4/

Answer 6

There's the blacklist package on npm which has a very flexible api.

Also a situational trick using the object rest-spread proposal (stage-3).

const {a, b, ...rest} = {a: 1, b: 2, c: 3, d: 4};
a // 1
b // 2
rest // {c: 3, d: 4}

This is often used in react components where you want to use a few properties and pass the rest as props to a <div {...props} /> or similar.