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Category: Javascript

  • Duplicate Object in JavaScript

    To create a duplicate of an object in JavaScript, you can use the Object.assign() method. This method creates a new object and copies the properties and values from one or more source objects into the new object. Here is an example of how you can use the Object.assign() method to create a duplicate of an…

  • Write JSON to File in Node.js

    To write JSON to a file in JavaScript, you can use the fs.writeFile() method from the fs module. This method takes a file path, the data to be written to the file, and a callback function that is executed when the write operation is complete. Here is an example of how you can use the…

  • How to Call JavaScript Function When Checkbox is Checked

    To call a JavaScript function when a checkbox is checked, you can use the onchange event. This event is triggered when the state of the checkbox is changed, either by the user or by your code. Here is an example of how you can use the onchange event to call a function when a checkbox…

  • 3 Ways to Square a Number in JavaScript

    The best way to square a number in JavaScript is to use the exponentiation operator (**). For example: This is preferred over using Math.pow because it is shorter and also works for BigInts. Method 1: Exponentiation Operator The ** operator is a relatively new addition to JavaScript that is used to raise a number to…

  • JavaScript Zero Pad Number

    In JavaScript, you can pad a number with leading zeros using the toString method and specifying a desired length for the resulting string. For example: In this example, we first convert the number 123 to a string using the toString method. We then call the padStart method on the resulting string, passing in two arguments:…

  • JavaScript “for in” vs “for of”

    In JavaScript, the for…in statement is used to loop over the properties of an object. It takes the form: where prop is a variable that will be set to the name of each property in the object as the loop iterates, and object is the object whose properties are being enumerated. For example: The for…of…

  • JavaScript URL Redirect

    To redirect a user to a new URL in JavaScript, you can use the window.location object and assign the new URL to its href property. For example: This will immediately redirect the user to the specified URL. Note that you should include the protocol (e.g., http, https) in the URL you are redirecting to. Alternatively,…

  • The Best Way to Check if Object is Empty in JavaScript

    The absolute best way to check if a given variable is an empty object in JavaScript is as follows: Yes, the code is more verbose than many other solutions you will find online that check the length of Object.keys. But, this solution is faster because it does not create a new array using Object.keys just…

  • Check if NULL in JavaScript

    To check if a variable is null in JavaScript, you can use the === or !== operators. For example: Or, using the !== operator: Keep in mind that null is a special value in JavaScript that represents an absence of value, whereas undefined represents a variable that has not been assigned a value. So, to…

  • Zipping Two Arrays in JavaScript

    Have you ever needed to combine the elements of two arrays into a single array? In JavaScript, this process is called zipping, and it can be easily achieved using the map() method. In this article, we will explore how to zip two arrays in JavaScript, with examples and explanations to help you understand the process.…

  • Aggregate Array of Objects by Key in JavaScript

    In this example, we are using the reduce() method to iterate over the objects in the sales array and group the values of the value property by the salesperson property. We are using an object as the accumulator, with the salesperson names as the keys and the sums of their sales as the values. For…

  • Aggregating Arrays in JavaScript: A Beginner’s Guide

    Are you looking to aggregate the data in your arrays in JavaScript? In this article, we will introduce the concept of array aggregation and explain how to use the reduce() method to perform this operation. We will also discuss other techniques for aggregating arrays and provide a practical example to illustrate how these techniques can…

  • JavaScript Yes/No Alerts

    JavaScript alerts are a helpful tool for web developers to communicate important information to their users. The “yes/no” alert is a specific type of JavaScript alert that presents users with a choice between two options: “OK” and “Cancel”. In this article, we will discuss how to create a JavaScript alert that offers a yes/no choice…

  • Escaping Quotes in JavaScript

    In JavaScript, quotes are used to define string values. However, sometimes you may need to use quotes within a string value. In this case, you’ll need to escape the quotes in order to prevent them from being interpreted as the end of the string value. In this article, we’ll explore how to escape quotes in…

  • JavaScript Object to Array

    JavaScript objects allow for storing a collection of key-value pairs. However, sometimes it may be necessary to work with an array instead. In this article, we’ll explore three methods for converting a JavaScript object to an array. Method 1: Object.entries() The first method for converting an object to an array is by using the Object.entries()…

  • Multiple Conditions in JavaScript If

    JavaScript is a powerful and popular programming language that allows developers to create complex and interactive websites. One of the key features of JavaScript is the ability to use the if statement to evaluate multiple conditions and take different actions based on the result. In this article, we will explore how to use the if…

  • JavaScript Splice vs. Slice: What’s the Difference?

    If you’re a JavaScript programmer, you’ve likely come across the splice and slice array methods. These methods are both used to extract elements from an array, but they differ in a few key ways. In this article, we’ll take a closer look at the splice and slice methods and how they differ from one another.…

  • Is JavaScript an Interpreted Language?

    JavaScript is a popular programming language that is used to build web applications. One question that often arises when discussing JavaScript is whether it is an interpreted language. In this article, we will answer this question and explore the characteristics of interpreted languages. What is an Interpreted Language? An interpreted language is a type of…

  • Appending to a List in JavaScript

    In JavaScript, a list is a collection of data items that are stored in a specific order. A list can be used to store any type of data, including numbers, strings, objects, and even other lists. In this article, we will explore how to add items to the end of a list in JavaScript. Using…

  • Is JavaScript a Backend Language?

    JavaScript is a popular programming language that is commonly used for building web applications. It is primarily known as a frontend language, meaning it is used for creating the user interface and handling user interactions on the client-side (i.e. the web browser). However, recent advancements in JavaScript technology have made it possible for JavaScript to…

  • Opening a Link in a New Tab in JavaScript

    In JavaScript, it is often necessary to open a link in a new tab or window. This can be useful for directing users to a new page or allowing them to view additional information without leaving the current page. In this article, we will explore how to open a link in a new tab in…

  • Grouping an Array of Objects by Key in JavaScript

    In JavaScript, it is often necessary to group an array of objects by a common key. This can be useful for organizing data, performing statistical analysis, or any number of other tasks. In this article, we will explore various techniques for grouping an array of objects by key in JavaScript. Using the Array.reduce() Method One…

  • Calculating the Average of Two Numbers in JavaScript

    In JavaScript, it is common to need to calculate the average of two or more numbers. In this article, we will explore various techniques for doing this in JavaScript. Using Basic Arithmetic One way to calculate the average of two numbers is to simply add the numbers together and then divide by 2. Here is…

  • Calculating the Average of an Array in JavaScript

    Working with arrays is a common task in JavaScript, and one common operation is to calculate the average of an array of numbers. In this article, we will explore how to do this using various techniques in JavaScript. Using a Loop to Calculate the Average One way to calculate the average of an array is…

  • Using Variables in Strings with JavaScript

    JavaScript is a versatile and widely-used programming language, and a key concept in JavaScript is the ability to use variables in strings. In this article, we will explore what this means and how it can be useful in your code. How to Use Variables in Strings To use a variable in a string, you must…

  • How to Check if Value is an Object in JavaScript

    In JavaScript, objects are a fundamental data type that is used to store and organize data. Objects are composed of key-value pairs, where the keys are used to identify and access the associated values. Objects are often used to represent real-world entities and their properties, and they are a powerful tool for organizing and manipulating…

  • JavaScript: Understanding the “Equals” Operator for Strings

    JavaScript is a powerful and widely-used programming language, and understanding its core concepts is crucial for any developer. One of the key concepts in JavaScript is the “equals” operator, which is used to compare values and determine if they are equal to one another. In this article, we will take a closer look at how…

  • Comparing Arrays in JavaScript

    Arrays are a fundamental data structure in many programming languages, including JavaScript. An array is a container that holds a fixed number of values in a specific order. In JavaScript, arrays are a versatile and useful tool for storing and manipulating data. In this article, we will explore the concept of comparing arrays in JavaScript…

  • Comparing to undefined in JavaScript: Pitfalls to Avoid

    JavaScript is a popular programming language that is often used for building web applications. In JavaScript, the undefined value is a primitive value that represents the absence of a value or the lack of existence of a variable. In this article, we will explore the concept of comparing values to undefined in JavaScript and discuss…

  • How Long Does it Take to Learn JavaScript and Get a Job?

    Learning JavaScript can open up a wide range of career opportunities, from entry-level positions as a junior developer to more advanced roles as a full-stack developer or software engineer. But how long does it take to learn JavaScript and get a job? The answer to this question depends on a variety of factors, including your…

  • JavaScript $.get Example: Sending HTTP GET Requests with jQuery

    In JavaScript, the $.get() method is a shorthand for the jQuery $.ajax() method, and it can be used to send an HTTP GET request to a server to retrieve data. In this article, we’ll take a closer look at how to use the $.get() method, and explore some examples of how to send GET requests…

  • Where Does JavaScript Go in HTML?

    JavaScript is a powerful and versatile programming language that is commonly used to add interactive features to web pages. But when it comes to writing JavaScript code in an HTML document, there are a few different options available. In this article, we’ll take a closer look at where JavaScript code should go in an HTML…

  • Executing JavaScript After Page Load: Best Practices and Techniques

    In JavaScript, it’s common to write code that should be executed only after the web page has finished loading. This is typically necessary for two reasons: In this article, we’ll explore some common ways to execute JavaScript code after a web page has loaded, and discuss some best practices for optimizing the performance of our…

  • “var” vs “let” in JavaScript

    When it comes to declaring variables in JavaScript, there are two main keywords that we can use: var and let. While these keywords may seem interchangeable at first glance, they actually have some important differences that every JavaScript programmer should be aware of. In this article, we’ll take a closer look at the var and…

  • Breaking Out of a forEach Loop in JavaScript

    In JavaScript, the forEach method allows us to iterate over an array and perform a specific operation on each element in the array. However, there are times when we might want to stop the forEach loop before it has completed iterating over the entire array. In this article, we will explore how to do this…

  • Using the XOR Operator in JavaScript

    In JavaScript, the XOR operator (^) allows you to perform a logical exclusive OR operation on two operands. The XOR operator returns true if one of the operands is true and the other operand is false, and it returns false if both operands are true or if both operands are false. In this article, we’ll…

  • Getting the Current Year in JavaScript

    In JavaScript, you may need to get the current year for various purposes, such as displaying the year in a copyright notice or using it in a date calculation. In this article, we’ll take a look at how to get the current year in JavaScript and discuss some best practices for using it in your…

  • Checking if a Number is Between Two Numbers in JavaScript

    In JavaScript, you may need to check if a number falls within a specific range of numbers. For example, you may want to ensure that a user-entered number is between a minimum and maximum value, or you may want to check if a random number is within a certain range. In this article, we’ll take…

  • Using HTTP GET with JavaScript

    JavaScript is a popular programming language that is used for web development. One common task in web development is making HTTP requests to retrieve data from a server. In this article, we’ll take a look at how to use the HTTP GET method with JavaScript to fetch data from a server. The HTTP GET Method…

  • The Best JavaScript IDEs for Mac Users

    With so many options available, it can be difficult to choose the right JavaScript IDE (Integrated Development Environment) for your needs. Here, we’ll take a look at some of the best options for Mac users and highlight their key features. Introduction JavaScript is a popular programming language that is used for web development, server-side scripting,…