Add Key Value To Javascript Object Code Example

Example 1: js add key to object

// given const obj = {     key1: value1,     key2: value2 };  // add pair obj["key3"] = value3; obj.key4 = value4;

Example 2: how to add field to object in js

// original object { key1: "a", key2: "b"} var obj = {     key1: "a",     key2: "b" };  // adding new filed - you can use 2 ways obj.key3 = "c"; // static // or obj["key3"] = "c"; // dynamic - 'key3' can be a variable console.log(obj) // {key1: "a", key2: "b", key3: "c" }

Example 3: javascript add to object

var element = {}, cart = []; element.id = id; element.quantity = quantity; cart.push(element);  // Array of Objects in form {element: {id: 10, quantity: 10} } var element = {}, cart = []; element.id = id; element.quantity = quantity; cart.push({element: element});

Example 4: add new key value pair to object javascript

const person = { 	name: "Elon Musk" }  person.age = 49;  console.log(person); // {name: "Elon Musk", age: 49}