JavaScript Object.getOwnPropertyNames() Example

The Object.getOwnPropertyNames() method returns an array of all properties (including non-enumerable properties except for those which use Symbol) found directly in a given object.

Syntax

Object.getOwnPropertyNames(obj)

Parameters

obj - The object whose enumerable and non-enumerable properties are to be returned.

Return value

An array of strings that corresponds to the properties found directly in the given object.

Examples

Example 1 - Retrieve all properties of the User object

function User(firstName, lastName, emailId, age){
    this.firstName = firstName;
    this.lastName = lastName;
    this.emailId = emailId;
    this.age = age;
}

console.log(Object.getOwnPropertyNames(new User()));

Output:

["firstName", "lastName", "emailId", "age"]

Example 2 - Iterate and print User object properties and values

function User(firstName, lastName, emailId, age){
    this.firstName = firstName;
    this.lastName = lastName;
    this.emailId = emailId;
    this.age = age;
}

var user = new User("Ramesh", "Fadatare", "[email protected]", 29);
console.log(Object.getOwnPropertyNames(user));

// Logging property names and values using Array.forEach
Object.getOwnPropertyNames(user).forEach(
  function (val, idx, array) {
    console.log(val + ' -> ' + user[val]);
  }
)

Output:

["firstName", "lastName", "emailId", "age"]
firstName -> Ramesh
lastName -> Fadatare
emailId -> [email protected]
age -> 29

References

• JavsScript MDN - Object.getOwnPropertyNames() Method