Sometimes, we want to remove undefined fields from an object with JavaScript

In this article, we’ll look at how to remove undefined fields from an object with JavaScript.

How to remove undefined fields from an object with JavaScript?

To remove undefined fields from an object with JavaScript, we can use the Object.keys method to get the keys of the object.

Then we call forEach with a callback that removes the undefined properties.

For instance, we write

Object.keys(obj).forEach((key) => {
  if (obj[key] === undefined) {
    delete obj[key];
  }
});

to get the obj object’s keys with Object.keys.

Then we call forEach with a callback to check if each object property is undefined with

obj[key] === undefined

And if it’s true, we use delete to remove the property.

Conclusion

To remove undefined fields from an object with JavaScript, we can use the Object.keys method to get the keys of the object.

Then we call forEach with a callback that removes the undefined properties.