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Javascript Object

In JavaScript, objects are one of the fundamental data types, and they play a central role in the language. Objects are used to store collections of key-value pairs, where each key is a unique string (or symbol) and each value can be any data type, including other objects.


					let obj = {
    key1: value1,
    key2: value2,
    // More key-value pairs


Key Characteristics:

    1. Key-Value Pairs:

      • Objects consist of a set of key-value pairs, where each key is a string (or symbol) and each value can be any data type, including other objects.
  • Dynamic Properties:

    • Properties (keys and values) can be added, modified, or deleted from an object dynamically, allowing for flexible data manipulation
  • Accessing Properties:

    • Properties can be accessed using dot notation (obj.key) or bracket notation (obj['key']). Bracket notation is necessary when the key contains special characters or when it’s dynamically generated.
  • Iteration:

    • Objects are iterable, allowing you to loop through their properties using various methods like for...in loop, Object.keys(), Object.values(), or Object.entries().
  • Data Types:

    • Values in objects can be of any data type, including primitive types (such as numbers, strings, booleans) and complex types (such as arrays, functions, and other objects).

Example Usage:

					let person = {
    name: "John",
    age: 30,
    isStudent: false,
    greet: function() {
    console.log("Hello, my name is 
    + this.name);

// Output: John
// Output: Hello, my name is John

// Adding a new property dynamically
person.location = "New York";
// Output: New York

// Looping through object properties
for (let key in person) {
    console.log(key + ": "
    + person[key]);



    • Object.keys(obj):
      • Returns an array containing the keys of the object.
  • Object.values(obj):
    • Returns an array containing the values of the object.
  • Object.entries(obj):
    • Returns an array of arrays containing key-value pairs of the object.

Use Cases:

  • Storing and organizing related data and functionality.
  • Passing complex data structures between functions and modules.
  • Implementing key-value stores, dictionaries, or associative arrays.