Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Articles on Trending Technologies
Technical articles with clear explanations and examples
The HashTable Class in Javascript
A HashTable (Hash Map) is a data structure that stores key-value pairs using a hash function to compute array indices. This implementation uses chaining to handle collisions, where multiple values can be stored at the same index using arrays. Complete HashTable Implementation class HashTable { constructor() { this.container = []; // Populate the container with empty arrays // which can be used to add more elements in // cases of collisions for (let i = ...
Read MorePreventDefault( ) vs Return false in JavaScript?
In JavaScript, when handling events, you often need to prevent the default browser behavior. The two common approaches are preventDefault() and return false, but they work differently. The preventDefault() method stops only the default action, while return false stops both the default action and event propagation. Key Differences preventDefault() return false Method available on event objects JavaScript statement that can be used anywhere Stops only the default behavior Stops default behavior AND event propagation Allows event to continue bubbling up Stops event bubbling and function execution ...
Read MoreIs there an elegant way of passing an object of parameters into a function?
Passing an object of parameters to a function provides flexibility and improves code readability. This technique allows you to avoid positional parameters and makes your functions more maintainable. Using Object Destructuring (Recommended) The most elegant approach uses ES6 destructuring to extract object properties directly in the function parameter: Object Parameters Example Passing Object Parameters to Functions Calculate Sum ...
Read MoreRemove and add new HTML Tags with JavaScript?
JavaScript provides several methods to dynamically remove and add HTML elements to the DOM. You can hide/show existing elements or completely remove/create new elements using vanilla JavaScript or jQuery. Method 1: Using jQuery hide() and show() The simplest approach is using jQuery's hide() and show() methods to toggle element visibility: Hide/Show Elements Test JavaScript This content can be hidden and shown. ...
Read MoreCheck for illegal number with isNaN() in JavaScript
In JavaScript, isNaN() function checks if a value is "Not a Number" (NaN). It's commonly used to validate numeric operations and detect illegal numbers in calculations. What is NaN? NaN stands for "Not a Number" and is returned when a mathematical operation fails or produces an undefined result, such as multiplying a string with a number. Syntax isNaN(value) Parameters value: The value to be tested. If not a number, JavaScript attempts to convert it before testing. Return Value Returns true if the value is NaN, false otherwise. Example: Detecting ...
Read MoreFinding mistakes in a string - JavaScript
We are required to write a JavaScript function that takes in two strings. The first string is some mistyped string and the second string is the correct version of this string. We can assume that the two strings we are getting as argument will always have the same length. We have to return the number of mistakes that exist in the first string by comparing it character by character with the correct version. Approach The solution involves iterating through both strings simultaneously and comparing each character at the same position. When characters don't match, we increment our ...
Read MoreThrice sum of elements of array - JavaScript
We are required to write a JavaScript function that takes in an array of Numbers and returns a new array with elements as sum of three consecutive elements from the original array. For example, if the input array is: const arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] Then the output should be: const output = [3, 12, 21, 9]; The function groups elements in sets of three and calculates their sum: (0+1+2=3), (3+4+5=12), (6+7+8=21), and (9+0+0=9) for the remaining element. How It Works The ...
Read MoreHow to add 2 hours to a JavaScript Date object?
In this tutorial, we will learn how to add 2 hours to a JavaScript Date object. Here we will discuss two methods which are following. Using the getTime() Method Using the setHours() Method Using the getTime() Method JavaScript date getTime() method returns the numeric value corresponding to the time for the specified date according to universal time. The value returned by the getTime() method is the number of milliseconds since 1 January 1970 at 00:00:00. Syntax Date.getTime() Approach To add 2 hours to the Date Object first, we get ...
Read MoreWhich event occurs in JavaScript when an element's content is cut?
The oncut event occurs when an element's content is cut using Ctrl+X or the right-click context menu. This event is commonly used with input fields, textareas, and other editable elements to track when users cut text. Syntax element.oncut = function() { // Code to execute when content is cut }; // Or using addEventListener element.addEventListener('cut', function(event) { // Code to execute when content is cut }); Example: Basic oncut Event Cut Event Example ...
Read MoreDraw part of an image inside HTML5 canvas
Drawing part of an image in HTML5 canvas is useful for creating sprites, animations, or displaying specific portions of larger images. The key is using the extended drawImage() method with clipping parameters. Syntax context.drawImage(image, sx, sy, sWidth, sHeight, dx, dy, dWidth, dHeight); Parameters Parameter Description sx, sy Starting coordinates in source image sWidth, sHeight Width and height of clipped area in source dx, dy Destination coordinates on canvas dWidth, dHeight Size to draw on canvas Example: Drawing Part of an Image ...
Read More