Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
In this article, you will understand how to add an element to a JSON object using JavaScript. JSON object literals are keys and values are separated by a colon surrounded by curly braces {}. Example 1 In this example, we add an element to a json object using bracket notation, var jsonObject = { members: { host: "hostName", viewers: { userName1: "userData1", ... Read More
The task is to check whether the array contains a particular value. Also, we need to check if the array contains the particular object with the given property. This tutorial will use the array.includes(), and array.some() method to check whether the array contains the value or object with a particular property. Use the array.includes() method to check values exist in the array The array.includes() method allows us to check whether the array contains any value. In simple terms, we can search for values in the array using the array.includes() method. Syntax Users can follow the syntax below to use the ... Read More
We will learn to swap two variable values in JavaScript using various approaches. Let’s understand via example what swapping means. For example, we have two variables called variable1 and variable2. When we assign the values of variable2 to variable1 and the value of variable1 to variable2, we can say that we have swapped the values of variable1 and variable2. Use the temporary variable We can create a temporary variable, which means any variable to store the value of the first variable temporarily. After that, we can assign the value of the second variable to the first variable. Next, we can ... Read More
In this article, you will understand how to access object properties from result returned by async() functions in JavaScript. An object property in JavaScript is a variable that is associated with the object itself, i.e. the properties have a name and value is one of the attributes linked with the property. Example 1 In this example, let’s understand how to access objects property using dot notation console.log("A function is created that returns promise object") const promiseFunction = (input) => { return new Promise((resolve, reject) => { return resolve({ ... Read More
Sometimes, we require sorting the options of the dropdown menu in alphabetical order. For example, you are selling computers on your website, and you want to allow users to select a computer based on the model. If your website contains hundreds of models of different brands, it will be hard for users to find a computer with a particular brand if it is not sorted. However, you can provide the search functionality but if it’s not there, then sorting all the option elements in alphabetical order is better. Here, we will learn various approaches to sort all options of the ... Read More
In this article, you will understand how to calculate days left until next Christmas using JavaScript. The Date object works with dates and times. Date objects are created with new Date(). JavaScript will use the browser's time zone and display a date as a full text string. Example 1 In this example, we compute the time difference without functions. let todayDate = new Date(); console.log("Today's date is defined as: ", todayDate) let christmasYear = todayDate.getFullYear(); if (todayDate.getMonth() == 11 && todayDate.getDate() > 25) { christmasYear = christmasYear + 1; } let christmasDate = new Date(christmasYear, 11, ... Read More
Now, the question is why we need to create a query parameter using JavaScript. Let’s understand it via real-life examples. For example, if you go on amazon’s website and search for any product, you will see that it automatically appends your search query to the URL. It means we require to generate the query params from the search query. Also, we can allow users to select any value from the dropdown option. We can generate query parameters and redirect users to a new URL based on the selected value to get results. We will learn to create a query parameter ... Read More
In this article, you will understand how to calculate local time in Node.js. The Date object works with dates and times. Date objects are created with new Date(). JavaScript will use the browser's time zone and display a date as a full text string. Node.js is an open-source and cross-platform JavaScript runtime environment.As an asynchronous event-driven JavaScript runtime, Node.js is designed to build scalable network applications. Example 1 In this example, we use the toDateString and toTimeString function const dateTimeObject = new Date(); console.log("A date-time object is created") console.log(`Date: ${dateTimeObject.toDateString()}`); console.log(`Time: ${dateTimeObject.toTimeString()}`); Output A date-time object is created ... Read More
Before we start, let’s understand the hash in JavaScript. The hash is also a string, but it's encrypted using a particular algorithm. Generally, we use the hash for security purposes. For example, Google stores users' emails and passwords in their database. Now, Google’s employees can access their database for development purposes. But can they get the user’s email and password from the database? No, because the password is stored in the hash form, and to decrypt the password, the employee needs the key which we used while creating the hash from the password string. So, in such a way, we ... Read More
In this article, you will understand how to add a property to a JavaScript object using a variable as the name. Adding property to an object can be achieved by two methods. The first is the dot (.) notation and the second is using the brackets([]). Example 1 In this example, let’s use the dot (.) notation. var inputObject = {a: "value1"}; console.log("An object is created with properties: ", inputObject) inputObject.b = "value2"; console.log("After adding properties, the object now contains: ", inputObject) console.log(inputObject) Explanation Step 1 − Define an object namely inputObject. Step 2 − Add an ... Read More