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Arrays in JavaScript

Introduction to JavaScript
What is JavaScript? How it works? History of JavaScript
Basic Concepts in JavaScript
Variables Data Types Operators Control Flow
Functions and Data Structures
Functions Builtin functions Userdefined functions Parameters and Arguments Arrays Indexes and length Array methods
ObjectOriented JavaScript
Object and Properties Constructors Inheritance Prototype
DOM Manipulation
What is DOM? Accessing HTML elements with JavaScript Manipulating HTML elements with JavaScript Events and event handling
Asynchronous JavaScript
Callbacks Promises Async/await Asynchronous data loading AJAX
jQuery
What is jQuery? Selecting and manipulating HTML elements with jQuery jQuery events
Browser APIs
Working with Web Storage Location API Navigator API Geolocation API Canvas API
Expressions and Regular Expressions
Boolean expressions Regular expressions
Debugging and Testing JavaScript
Debugging basics Chrome Developer Tools Unit testing Testing frameworks
JavaScript Libraries and Frameworks
Introduction to libraries and frameworks React.js Angular.js Vue.js Node.js
Deploying JavaScript Applications
Deploying for the Web Hosting options
Ecmascript6 Features
Classes Arrow functions Promises Destructuring of Objects and Arrays Default parameters and Spread Operator
Security and Best Practices in JavaScript
Security basics Best practices for writing safe and maintainable JavaScript code Code optimization techniques
Conclusion
Recap of the course Next Steps.

Arrays

52

#description

Arrays are a fundamental data structure in JavaScript that allows you to store and manipulate a collection of elements of the same type. Each element in the array is identified by its index, which starts from zero.

To create an array, you can use the array literal notation which uses square brackets:

 
                    
let arr = []; // empty array
let nums = [1, 2, 3, 4, 5]; // array of numbers
let names = ["Alice", "Bob", "Charlie"]; // array of strings

You can access the elements of an array using the square bracket notation:

 
                    
console.log(nums[0]); // output: 1
console.log(names[2]); // output: "Charlie"

You can also change the value of an element by assigning a new value to its index:

 
                    
nums[0] = 6;
console.log(nums); // output: [6, 2, 3, 4, 5]

Arrays have several built-in methods that allow you to manipulate their contents:

 
                    
nums.push(6); // add 6 to the end of the array
console.log(nums); // output: [1, 2, 3, 4, 5, 6]

nums.pop(); // remove the last element from the array
console.log(nums); // output: [1, 2, 3, 4, 5]

names.shift(); // remove the first element from the array
console.log(names); // output: ["Bob", "Charlie"]

names.unshift("Alice"); // add "Alice" to the beginning of the array
console.log(names); // output: ["Alice", "Bob", "Charlie"]

You can also use loops to iterate over the elements of an array:

 
                    
for(let i = 0; i < nums.length; i++) {
    console.log(nums[i]);
}

nums.forEach(function(num) {
    console.log(num);
});

Arrays are an essential data type in JavaScript and are widely used in building applications ranging from simple web pages to complex web applications, games, and more.

March 25, 2023

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