Let’s say the following is our string in dot notation −const keys = "details1.details2.details3.details4.details5"And the following is our array −const firsName = "David";To turn into a nested object, use the concept of split(‘.’) along with map().ExampleFollowing is the code −const keys = "details1.details2.details3.details4.details5" const firsName = "David"; var tempObject = {}; var container = tempObject; keys.split('.').map((k, i, values) => {    container = (container[k] = (i == values.length - 1 ? firsName : {})) }); console.log(JSON.stringify(tempObject, null, ' '));To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo227.js.OutputThe output is as ... Read More

Let’s say we are getting two values with prompt −var firstvalue = parseInt(prompt("Enter the value1")); var secondvalue = parseInt(prompt("Enter the value2"));ExampleFollowing is the code − Live Demo            Document    var firstvalue = parseInt(prompt("Enter the value1"));    var secondvalue = parseInt(prompt("Enter the value2"));    if (firstvalue * secondvalue > 50)       document.write("Result is correct");    else       document.write("Result is not correct"); To run the above program, save the file name anyName.html (index.html). Right click on the file and select the option “Open ... Read More

Finding specific words in an array is a common task in JavaScript, especially when you need to filter data, search through lists, or analyze text. An array is a simple and fundamental data structure in JavaScript that stores multiple values of the same data type. JavaScript has several built-in methods, like includes(), filter(), and find(), that help you search for specific words easily. This article will explain these methods with examples. Finding Specific Words in an Array Finding specific words in an array can be done in the following ways: Using includes() method Using filter() method Using find() ... Read More

You cannot change the value of an object when it is defined using const keyword.After changing it will remain same.Let’s say the following is our variable defined with const −const details1 = {    firstName: 'David',    subjectDetails: { subjectName: 'JavaScript' } }ExampleFollowing is the code to change the const variable, which would only display the initial value −const details1 = {    firstName: 'David',    subjectDetails: { subjectName: 'JavaScript' } } const details2 = { ...details1, subjectDetails: { ...details1.subjectDetails }, firstName: 'David' } details2.subjectDetails.subjectName = 'Java ' console.log(details1);To run the above program, you need to use the following command ... Read More

Let’s say the following are our objects −var object1 = { firstName: "David" }; var object2 = { firstName: "David" };You will not get the correct result using comparison operator (== or ===). Use JSON.stringify() for this.ExampleFollowing is the code implementing both the ways and showing the correct result −var object1 = { firstName: "David" }; var object2 = { firstName: "David" }; if (object1 == object2)    console.log("using == operator result ==> true"); else    console.log("using == operator result ==> false"); if (JSON.stringify(object1) == JSON.stringify(object2))    console.log("using JSON.stringify() operator result ==> true"); else    console.log("using JSON.stringify() operator result ==> ... Read More

Let’s say the following are our array of objects:const details =    [       {          employeeFirstName: "John",          employeeLastName: "Doe"       },       {          employeeFirstName: "David",          employeeLastName: "Miller"       },       {          employeeFirstName: "John",          employeeLastName: "Smith"       }    ]ExampleFollowing is the code to fetch specific values, in this case with first name “John” −const details =    [       {     ... Read More

Let’s say the following is our array object −var arrayObject =    [       "John",       "David",       "Mike"    ]Use length property to set the length to 0 and clear memory.The syntax is as follows to clear memory and allocate again −yourArrayObjectName.length=0; // To clear memory yourArrayObjectName.length=4; // To allocate memoryExampleFollowing is the code −var arrayObject =    [       "John",       "David",       "Mike"    ] arrayObject.length = 0; console.log(arrayObject); arrayObject.length = 5; for (var i = 0; i < arrayObject.length; i++)    console.log(arrayObject[i]);To run the ... Read More

To fetch alternative values, use the array index and check with the following condition −if(index%2==0) { // code } The above will display the even values.ExampleFollowing is the code −var subjectsName=["MySQL","JavaScript","MongoDB","C","C++","Java"]; for(let index=0;index node demo222.js Subject name at even position=MySQL Subject name at even position=MongoDB Subject name at even position=C++

Use get keyword to make getter function.ExampleFollowing is the code −const studentDetails = {    studentName: "David Miller",    get studentName() {       console.log('I am calling the getter method...')    } } console.log(studentDetails.studentName);To run the above program, you need to use the following command −The output is as follows −node fileName.js.Here, my file name is demo221.js.OutputThe output is as follows −PS C:\Users\Amit\JavaScript-code> node demo221.js I am calling the getter method... Undefined

For this, use the “this” keyword.ExampleFollowing is the code −class Employee {     constructor() {         this.tempObject = [             {                 firstName: "David",                 setTheAnotherFirstName() {                     this.firstName = "Carol";                 },             },         ];     } } var empObject = new Employee(); empObject.tempObject[0].setTheAnotherFirstName(); console.log("The Change First Name is=" + empObject.tempObject[0].firstName);To run the above program, you need to use the following command −node fileName.js. Here, my file name is demo220.js.OutputThe output is as follows −PS C:\Users\Amit\JavaScript-code> node demo220.js The Change First Name is=Carol