6 Ways to Delete a Property In JavaScript You Must Know

You might ask yourself how can I remove a property from a JavaScript object? I've found myself in this situation countless times.

In this article, I take you through 6 ways to achieve this. It's worth mentioning many of these techniques are exactly applicable even when you use a framework or at least you'll use a very similar approach there too.

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Let's get started.

1. The first way is to just use the delete operator. It's pretty simple and straightforward:

let myObject = { x: 1, property: 'something'};
delete myObject.property;

2. Another way to remove a property is to use the Object.assign() method which creates a new object without the property you wanted to remove.

const newObject = Object.assign({}, myObject);
delete newObject.property;

This method is commonly used when you want to maintain immutability of the original object and not change it. This approach is much more preferred to just using the delete operator.

3. You can also use the Object.entries() method to remove a property from an object. This method returns an array of arrays containing the key-value pairs of an object. You can then use the filter() method to exclude the key-value pair that you want to remove.

const newObject = Object.fromEntries(
  Object.entries(myObject).filter(([key]) => key !== 'property')
);

It's better to use this approach if you also want to do some extra processing on the object.

4. Another way of deleting a property is using the spread operator ... to create a new object and exclude the property that you want to remove. I've found this approach especially common among React developers.

const { property, ...newObject } = myObject;

5. For removing deeply nested properties, you can use the fantastic lodash library's method _.unset(object, 'path.to.property')

import _ from 'lodash';
_.unset(myObject, 'path.to.property');

6. Finally, if the property is not known until runtime, you can use the object[property name] to delete it.

const property = 'aProperty'; // value is set at runtime
delete myObject[property]

Top comments (4)

Jon Randy 🎖️ • Jan 12 '23 • Edited

Why on earth would you use eval? Why not just:

const property = 'aProperty'
delete myObject[property]

Also, the only way to delete a property from an object is to use delete, or a library that is using it (as in your lodash example). All other examples above are making a copy of the object, excluding the property you are trying to 'delete' - this is not the same thing at all. You're comparing apples and oranges.

You could also use delete on a copy of the original object - that would arguably be the most 'readable' way to make a new object without the property... but not very efficient if you wanted to create an object excluding multiple properties.