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Basic Objects in JavaScript (Simple)

Objects in JavaScript store data as key–value pairs.

Creating an Object

const obj = {};

Or with initial properties:

const obj = {
  firstName: "Edward",
  age: 24,
  cars: ["Audi", "BMW"],
  siblings: {
    sister: "Kim",
    brother: "Jeremy"
  }
};

Accessing Properties

Dot Syntax

console.log(obj.firstName);      // "Edward"
console.log(obj.age);            // 24
console.log(obj.siblings.brother); // "Jeremy"

Bracket Syntax

console.log(obj["firstName"]);       // "Edward"
console.log(obj["siblings"]["sister"]); // "Kim"

Use bracket syntax when property names are dynamic or contain special characters:

const specialObj = {
  "!note": "This is an exclamation",
  "1hello": "Starts with a number"
};

console.log(specialObj["!note"]);   // "This is an exclamation"
console.log(specialObj["1hello"]);  // "Starts with a number"

Values Can Be Anything

Primitives (string, number, boolean, null, undefined, Symbol)
Arrays
Other objects
Functions

const mixed = {
  text: "hello",
  count: 3,
  flag: true,
  data: null,
  items: [1, 2, 3],
  nested: { a: 1 },
  fn: function() { console.log("I’m a function!"); }
};

Summary

Objects group related data under named keys.
Use dot or bracket syntax to read/write properties.
Keys must be unique within the same object.
Values can be any valid JavaScript type.

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Array Iteration: Using `for...of` in JavaScript

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Basic Objects in JavaScript (Simple)

In this lesson, you'll discover the fundamentals of JavaScript objects, learning how to create, access, and manipulate data stored as key-value pairs. By the end, you'll be equipped to use both dot and bracket syntax to handle diverse data types, empowering you to manage complex structures with ease.

5m 8s