Remove all Undefined Values from an Object in JavaScript

Remove all Undefined Values from an Object in JavaScript #

To remove all undefined values from an object:

1. Use the Object.keys() method to get an array of the object's keys.
2. Use the forEach() method to iterate over the array and delete all undefined values using the delete operator.

Copied!
const obj = {
  a: undefined,
  b: 'test',
  c: undefined,
};

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

console.log(obj); // 👉️ {b: 'test'}

The Object.keys method returns an array containing the object's keys.

Copied!
const obj = {
  a: undefined,
  b: 'test',
  c: undefined,
};

// 👇️ ['a', 'b', 'c']
console.log(Object.keys(obj))

The Array.forEach method allows us to iterate over the array of keys.

We check if the value, associated to the current key is equal to undefined and if the condition is met, we use the delete operator to delete the key-value pair.

To remove all undefined values from an object:

1. Use the for...in loop to iterate over the object.
2. On each iteration, check if the value is equal to undefined and delete the value if it satisfies the condition.

Copied!
// Supported in IE

const obj = {
  a: undefined,
  b: 'test',
  c: undefined,
};


for (const key in obj) {
  if (obj[key] === undefined) {
    delete obj[key];
  }
}

console.log(obj); // 👉️ {b: 'test'}

The for...in loop allows us to iterate over the object's properties.

We check if the value of the current property is equal to undefined and if either condition is satisfied, we delete the key-value pair.

Further Reading #

• Get the Number of Keys in an Object using JavaScript
• Check if an Object contains a Function in JavaScript
• Get a Random Property from an Object in JavaScript
• Get a Random Property from an Object in JavaScript
• How to get the Length of an Object in JavaScript
• Check if a Map has an Object Key using JavaScript
• How to Rename an Object's Key in JavaScript
• Check if a Value is an Object using JavaScript
• Convert an Object to an Array using JavaScript
• Convert a JSON String to Object using JavaScript
• Convert an Array to an Object using JavaScript
• Create an Object from Two Arrays in JavaScript
• Solve - Cannot convert undefined or null to Object in JS