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
Object Oriented Programming Articles
Page 140 of 589
How to calculate the average in JavaScript of the given properties in the array of objects
We have an array of objects. Each object contains a few properties and one of these properties is age: const people = [ { name: 'Anna', age: 22 }, { name: 'Tom', age: 34 }, { name: 'John', ...
Read MoreJavaScript Check for case insensitive values?
JavaScript provides several methods to check for case insensitive values. The most common approaches use toLowerCase(), toUpperCase(), or regular expressions. Using toLowerCase() Method Convert both values to lowercase before comparison: let name1 = "JOHN"; let name2 = "john"; console.log(name1.toLowerCase() === name2.toLowerCase()); // true console.log("Hello".toLowerCase() === "HELLO".toLowerCase()); // true true true Using Regular Expression Use the i flag for case insensitive matching: let allNames = ['john', 'John', 'JOHN']; let makeRegularExpression = new RegExp(allNames.join("|"), "i"); let hasValue = makeRegularExpression.test("JOHN"); console.log("Is Present=" + hasValue); // Direct regex approach let ...
Read MoreHow to get odd and even position characters from a string?
In JavaScript, you can extract characters from odd and even positions in a string using various methods. This technique is useful for string manipulation tasks like creating puzzles, encoding, or data processing. Understanding the Problem Given a string, we want to separate characters based on their position index: Even positions (0, 2, 4...): "T", "i", " ", "s", " ", "a", " ", "e", "t", "!" Odd positions (1, 3, 5...): "h", "s", "i", "", "i", "", "t", "s", "" If the string is "This is a test!" Even positions: "Ti s a ...
Read MoreSplit Space Delimited String and Trim Extra Commas and Spaces in JavaScript?
When working with strings that contain multiple commas and spaces, you can use regular expressions with split() and join() methods to clean them up effectively. The Problem Consider this messy string with multiple consecutive commas and spaces: var sentence = "My, , , , , , , Name, , , , is John ,, , Smith"; console.log("Original string:", sentence); Original string: My, , , , , , , Name, , , , is John ,, , Smith Solution: Using Regular Expression with split() and join() The split(/[\s, ]+/) method splits ...
Read MoreTaking part from array of numbers by percent JavaScript
We have an array of number literals like this: const numbers = [10, 6200, 20, 20, 350, 900, 26, 78, 888, 10000, 78, 15000, 200, 1280, 2000, 450]; We need to write a function that takes an array of numbers and a percentage (0-100). The function should return the first n elements from the array that sum up to equal or just less than the specified percentage of the total array sum. Understanding the Problem Let's take a simpler example: const numbers = [12, 10, 6, 8, 4, 2, 8]; ...
Read MoreHow to do Butterfly Shuffle in JavaScript?
A butterfly shuffled array in JavaScript is an array of Numbers that is sorted such that the numbers decrease as we approach the center of array and increase as we approach the end of array. The biggest number is placed at the very first index. Another variation of butterfly shuffled array is where the numbers increase towards the center and decrease towards the end. In this case the smallest number is placed at the very first index. For people who come from a Mathematics background, it's somewhat relatable to the Gaussian distribution. Example Suppose we have ...
Read MoreHow to count a depth level of nested JavaScript objects?
We have an array of objects, which further have nested objects like this − const arr = [{ id: 0, children: [] }, { id: 1, children: [{ id: 2, children: [] }, { id: 3, children: [{ id: 4, children: [] }] }] }]; ...
Read MoreHow to split string when the value changes in JavaScript?
To split a string when the character value changes in JavaScript, you can use the match() method with a regular expression that captures consecutive identical characters. Syntax string.match(/(.)\1*/g) How the Regular Expression Works The pattern /(.)\1*/g breaks down as: (.) - Captures any single character \1 - Matches the same character as captured in group 1 * - Matches zero or more of the preceding element g - Global flag to find all matches Example var originalString = "JJJJOHHHHNNNSSSMMMIIITTTTHHH"; var regularExpression = /(.)\1*/g; console.log("The original string = ...
Read MoreIn JavaScript, need to perform sum of dynamic array
Let's say, we have an array that contains the score of some players in different sports. The scores are represented like this − const scores = [ {sport: 'cricket', aman: 54, vishal: 65, jay: 43, hardik: 88, karan:23}, {sport: 'soccer', aman: 14, vishal: 75, jay: 41, hardik: 13, karan:73}, {sport: 'hockey', aman: 43, vishal: 35, jay: 53, hardik: 43, karan:29}, {sport: 'volleyball', aman: 76, vishal: 22, jay: 36, hardik: 24, karan:47}, {sport: 'baseball', aman: 87, vishal: 57, jay: 48, hardik: 69, karan:37}, ]; We need to ...
Read MoreUpdate JavaScript object with another object, but only existing keys?
To update a JavaScript object with values from another object while only affecting existing keys, you can use hasOwnProperty() to check if a key exists in the source object before updating it. Example var markDetails1 = { 'marks1': 78, 'marks2': 65 }; var markDetails2 = { 'marks2': 89, 'marks3': 90 }; function updateJavaScriptObject(details1, details2) { const outputObject = {}; Object.keys(details1) .forEach(obj => outputObject[obj] ...
Read More