For this, use Object.assign(). Following is the code −Exampleconst details = {john:{'studentName':'John'}, david:{'studentName':'David'}, mike:{'studen tName':'Mike'}, bob:{'studentName':'Bob'}, carol:{'studentName':'Carol'}}, join_values = ['David', 'Carol'],    output = Object.assign(       {},       ...Object       .keys(details)       .map(key =>       ({[key]: {          ...details[key],          lastName: join_values.includes(details[key].studentName) ?          'Miller' : 'Smith'    }}))) console.log(output)To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo157.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo157.js {    john: ... Read More

We will be creating two buttons, one for Increment and another Decrement −On clicking Increment (+), user will be able to increment the number in input type numberOn clicking Decrement (-), user will be able to decrement the number in input type numberExample Live Demo Document + -    function increment() {       document.getElementById('demoInput').stepUp();    }    function decrement() {       document.getElementById('demoInput').stepDown();    } To run the above program, save the file name “anyName.html(index.html)” and right click on the file. Select the option ... Read More

Here, we have set “Aabout_us” and “Hhome_page” with incorrectly spellings as anchor text.You can use substring(1) along with innerHTML to remove the first character and display them correctly as “about_us” and “home_page” respectively.Example Live Demo Document Aabout_us Hhome_page    [...document.querySelectorAll('.linkDemo div a')].forEach(obj=>    obj.innerHTML=obj.innerHTML.substring(1)) To run the above program, save the file name “anyName.html(index.html)” and right click on the file. Select the option “Open with Live Server” in VS Code editor.OutputThis will produce the following output with the correct forms ... Read More

Let’s say the following are our arrays −var firstArray=[100, 200, 400]; var secondArray=[400, 100, 200];You can sort both the arrays using the sort() method and use for loop to compare each value as in the below code −Examplevar firstArray=[100, 200, 400]; var secondArray=[400, 100, 200]; function areBothArraysEqual(firstArray, secondArray) {    if (!Array.isArray(firstArray) || ! Array.isArray(secondArray) ||    firstArray.length !== secondArray.length)    return false;    var tempFirstArray = firstArray.concat().sort();    var tempSecondArray = secondArray.concat().sort();    for (var i = 0; i < tempFirstArray.length; i++) {       if (tempFirstArray[i] !== tempSecondArray[i])          return false;    }   ... Read More

To access nested JSON property based on another property’s value, the code is as follows −Examplevar actualJSONData = JSON.parse(studentDetails()), studentMarks = getMarksUsingSubjectName(actualJSONData, "JavaScript"); console.log("The student marks="+studentMarks); function getMarksUsingSubjectName(actualJSONData, givenSubjectName){    for(var tempObj of actualJSONData){       if(tempObj.subjectName = givenSubjectName){          return tempObj.marks;       }    } } function studentDetails(){    return JSON.stringify(       [          { firstName : "John", subjectName: "JavaScript", marks : 97 },          { firstName : "David", subjectName: "Java", marks : 98 }       ]    ); }To run the above ... Read More

To replace value from a specific position, use splice() in JavaScript. Following is the code −Examplevar changePosition = 2 var listOfNames = ['John', 'David', 'Mike', 'Sam','Carol'] console.log("Before replacing="); console.log(listOfNames); var name = 'Adam' var result = listOfNames.splice(changePosition, 1, name) console.log("After replacing="); console.log(listOfNames)To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo14.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo154.js Before replacing= [ 'John', 'David', 'Mike', 'Sam', 'Carol' ] After replacing= [ 'John', 'David', 'Adam', 'Sam', 'Carol' ]

Let’s say the following is our array −var numbers=[10,101,76,56,5,210,3,100];To find the smallest number, the code is as follows −Examplefunction findMinimumElementUsingRecursive(numbers) {    if (numbers.length==1){       return numbers[0];    }    else if(numbers[0]>numbers[1]) {       return findMinimumElementUsingRecursive(numbers.slice(1));    } else {       return       findMinimumElementUsingRecursive([numbers[0]].concat(numbers.slice(2)));    } } var numbers=[10,101,76,56,5,210,3,100]; console.log("The minimum element is="+findMinimumElementUsingRecursive(numbers));To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo152.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo152.js The minimum element is=3

To filter array by multiple strings, use for loop along with indexOf(). Following is the code −Examplevar details = [    'My first Name is John and last Name is Smith',    'My first Name is John and last Name is Doe',    'Student first Name is John and last Name is Taylor' ]; var isPresent; var records = []; var matchWords = ['John', 'Doe']; for (var index = 0; index < details.length; index++){    isPresent = true;    for (var outer = 0; outer< matchWords.length; outer++) {       if (details[index].indexOf(matchWords[outer]) === -1) {         ... Read More

To split a URL, use the split() method. Use toString() before that. Let us see an exampleExamplevar newURL="http://www.example.com/index.html/homePage/aboutus/"; console.log(newURL); var splitURL=newURL.toString().split("/"); console.log(splitURL);Above, we have set forward slash in the split() function, since we need to split the URL after every such slash.To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo150.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo150.js http://www.example.com/index.html/homePage/aboutus/[    'http:',    '',    'www.example.com',    'index.html',    'homePage',    'aboutus',    '' ]Read More

The plus(+) sign before the variables defines that the variable you are going to use is a number variable.In the below code, there is brief description about plus sign. Following is the code −Examplevar firstValue="1000"; console.log("The data type of firstValue ="+typeof firstValues); var secondValue=1000; console.log("The data type of secondValue ="+typeof secondValue); console.log("The data type of firstValue when + sign is used ="+typeof +firstValue); var output=+firstValue + secondValue; console.log("Addition is="+output);To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo149.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo149.js The data type ... Read More