Remove Null and Undefined Values from Object in JavaScript-Code Examples

const removeNullAndUndefinedValuesFromObject = obj => {
  // return a new object with only the truthy values
  return Object.keys(obj)
    .filter(key => obj[key])
    .reduce((acc, key) => {
      // copy each truthy value to the new object
      acc[key] = obj[key];
      return acc;
    }, {});
};

// given this object
const obj = {
  a: 1,
  b: null,
  c: undefined,
  d: 'hi'
};

console.log(removeNullAndUndefinedValuesFromObject(obj));
// { a: 1, d: 'hi' }

const removeNullAndUndefinedValues = (obj) => {
  // create a new object to store the values in
  const newObj = {};
  // loop over each key/value pair in the passed in object
  for (const [key, value] of Object.entries(obj)) {
    // if the value is not null or undefined, add it to the new object
    if (value !== null && value !== undefined) {
      newObj[key] = value;
    }
  }
  // return the new object
  return newObj;
};

const obj = {
  name: '🐶',
  age: undefined,
  color: 'brown',
  weight: undefined
};

// remove all undefined values from obj
Object.keys(obj).forEach(key => obj[key] === undefined && delete obj[key]);

console.log(obj); // { name: '🐶', color: 'brown' }

const obj = {
  name: 'John',
  age: undefined,
  gender: 'male'
};

// remove all undefined values from the object
Object.keys(obj).forEach(key => obj[key] === undefined && delete obj[key]);

console.log(obj);
// { name: 'John', gender: 'male' }