Object

Object is nothing but key value pairs.

Define an Object

./object.js

const user = {
  name: "Swayam",
  age: 21,
  weight: "70kg",
};

`Object.key()`

This method return the keys present in the Object.

const user = {
  name: "Swayam",
  age: 21,
  weight: "70kg",
};
 
const key = Object.keys(user);
console.log("Keys of the Object:", key);

Output:

Keys of the Object: [ 'name', 'age', 'weight' ]

`Object.values()`

const user = {
  name: "Swayam",
  age: 21,
  weight: "70kg",
};
 
// Object.values()
const values = Object.values(user);
console.log("Values of Object:", values);

Output:

Values of Object: [ 'Swayam', 21, '70kg' ]

`Object.entries()`

const user = {
  name: "Swayam",
  age: 21,
  weight: "70kg",
};
 
// Object.entries()
const entries = Object.entries(user);
console.log("Object:", entries);

`Object.hasOwnProperty()`

This retruns true or false depending on whether the key is present in Object or not.

const user = {
  name: "Swayam",
  age: 21,
  weight: "70kg",
};
const hasProp = user.hasOwnProperty("name");
const hasProp2 = user.hasOwnProperty("test");
console.log("Does user obj has name as key?", hasProp);
console.log("Does user obj has test as key?", hasProp2);

Output:

Does user obj has name as key? true
Does user obj has test as key? false

Object.assign()

const obj = {
  test1: "test1",
  test2: "test3",
  test3: "test3",
};
 
let newObj = Object.assign({}, obj, { myNewTest: "new Test" });
console.log("After using the New Object:", newObj);

Output:

After using the New Object: {
  test1: 'test1',
  test2: 'test3',
  test3: 'test3',
  myNewTest: 'new Test'
}

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