Let’s say the following is our start value −var startValue=10;Let’s say the following is our end value −var endValue=20;Use the for loop to fetch numbers between the start and end value −Examplevar startValue=10; var endValue=20; var total=''; function printAllValues(startValue, endValue){    for(var start=startValue;start < endValue ;start++){       total=total+start+", ... Read More

At first, declare and initialize the total variable with 0 and then you need to iterate over all the array and extract all the values of array and add up with the updated total variable.Let’s say the following is our array with numbers −var listOfValues = [10, 3, 4, 90, ... Read More

To capitalize only the first letter, use the concept of regular expression along with toUpperCase(). Since the toUpperCase() capitalize the entire string, we need to use Regex to only capitalize the first letter after colon.Let’s say the following is our string −var objectValues='fullName: john Smith';Here’s the complete code to capitalize ... Read More

To get objects with specific property, use the concept of reduce() on both arrays individually. You don’t need to concatenate. Let’s say the following are our objects with student name and student marksvar sectionAStudentDetails = [    {studentName: 'John', studentMarks: 78},    {studentName: 'David', studentMarks: 65},    {studentName: 'Bob', studentMarks: ... Read More

Use the concept of map() along with ternary operator (?). Following are our array of objects −let firstCustomerDetails = [    {firstName: 'John', amount: 100},    {firstName: 'David', amount: 50},    {firstName: 'Bob', amount: 80} ];    let secondCustomerDetails = [    {firstName: 'John', amount: 400},    {firstName: 'David', amount: ... Read More

To create an array from JSON data, use the concept of map() from JavaScript. Let’s say the following is our data −const studentDetails =[    {       name : "John"    },    {       name : "David"    },    {       name ... Read More

Yes, JavaScript now supports the “null coalescing” operator, but you can also use the concept of logical OR (||). The syntax is as follows −var anyVariableName=null; var anyVariableName=yourVariableName || yourActualValue;Examplevar fullName=null; console.log("The full name is="+fullName); var actualName=fullName || "David Miller"; console.log("The full name is="+actualName);To run the above program, you need ... Read More

For this, use a “prototype”. JavaScript objects inherit properties and methods from a prototype. For accessing variables, we have also used the “this” in JavaScript.Examplefunction Customer(fullName){    this.fullName=fullName; } Customer.prototype.setFullName = function(newFullName){    this.fullName=newFullName; } var customer=new Customer("John Smith"); console.log("Using Simple Method = "+ customer.fullName); customer.setFullName("David Miller"); console.log("Using Prototype Method ... Read More

Let’s say the following is our Unordered List (ul) −    JavaScript Remove        MySQL Remove        MongoDB Remove        Java Remove Above, you can see the “Remove” button with every li element. On clicking this button, you can remove any li element.Following is ... Read More

You can use the concept of Map(). In JavaScript, map has the key value concept in which key must be unique.We also need to use the join() method to join Map values. Following is the code −Examplelet queryStringAppendWithURL = new Map(); queryStringAppendWithURL.set("firstParamter", ["name=John", "age=23", "countryName=US"]); queryStringAppendWithURL.set("secondParamter", ["subjectName=JavaScript", "Marks=91"]); let appendValue ... Read More