Web development

The Short Answer There are several ways to check if a JavaScript string contains a substring. Here’s a short summary of the most notable ones. 1. string.indexOf() Use the indexOf() method. This method returns the index of the first occurrence of the substring in the string, or -1 if the substring is not found. For

The easiest way to remove a property from an object in JavaScript is by using the delete operator. For example, if you have an object called person with a property age, you can remove the age like this: After you run this code, the person object will no longer have an age property. Note that

To find (and not delete) duplicates in a JavaScript array, you can use this function: Example use: Output: To learn how the above approach works, and what alternatives exist, please keep on reading. This guide shows you ways to find array duplicates and show them instead of deleting them. Besides, you will learn what performance

To log colored text to the JavaScript console, call the console.log method and include special formatting code %c to colorize the log and pass the colorizing CSS code as the second argument. For example, to log text in red, you can use the %c formatting code, followed by the desired text and a CSS color

An array is one of the key data types in JavaScript. It allows you to store values in a common place where it’s easy to access the values. This is a comprehensive guide to looping through arrays in JavaScript. You will learn multiple different and useful ways in which you can iterate over arrays. Which

In JavaScript, the call() and apply() methods are both used to borrow and call a function on another object. The only difference between them is the way they accept arguments: Both methods are useful when borrowing functionality. To call a function of one object on another object you can use call() or apply(). This is

To toggle a boolean value in JavaScript, use the not operator (!). This operator negates the boolean value, so if the value is true, it will become false, and if the value is false, it will become true. Here’s an example of how to toggle a boolean: Output: What Is the Not (!) Operator in

In JavaScript the difference between throw Error and throw new Error is that: When it comes to behavior, there’s really no difference between throw Error and throw new Error. For example: But the more technically correct way to throw a new Error object is by using the throw new Error instead of throw Error. Also,