Found 9313 Articles for Object Oriented Programming

Update JavaScript object with another object, but only existing keys?

AmitDiwan
Updated on 11-Sep-2020 07:02:32

786 Views

For this, use hasOwnProperty(). Following is the code −Examplevar markDetails1 ={    'marks1': 78,    'marks2': 65 }; var markDetails2 ={    'marks2': 89,    'marks3': 90 } function updateJavaScriptObject(details1, details2) {    const outputObject = {};    Object.keys(details1)    .forEach(obj => outputObject[obj] =    (details2.hasOwnProperty(obj) ? details2[obj] : details1[obj]));    return outputObject; } console.log(updateJavaScriptObject(markDetails1, markDetails2));To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo140.js.OutputThis will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo140.js { marks1: 78, marks2: 89 }

How to split string when the value changes in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:52:03

128 Views

For this, you can use match() along with regular expression. Following is the code −Examplevar originalString="JJJJOHHHHNNNSSSMMMIIITTTTHHH"; var regularExpression=/(.)\1*/g; console.log("The original string="+originalString); var splitting=originalString.match(regularExpression); console.log("After splitting the original string="); console.log(splitting);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo139.js.OutputThis will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo139.js The original string=JJJJOHHHHNNNSSSMMMIIITTTTHHH After splitting the original string=[    'JJJJ', 'O',    'HHHH', 'NNN',    'SSS', 'MMM',    'III', 'TTTT',    'HHH' ]

How to find the second largest element in a user-input JavaScript array?

AmitDiwan
Updated on 11-Sep-2020 06:50:14

442 Views

Let’s say following is our array −var numbers=[10,50,80,60,89];To find the second largest element, the code is as follows −Examplevar numbers=[10,50,80,60,89]; var firstLargerNumber = Number.MIN_SAFE_INTEGER; var secondlargerNumber = firstLargerNumber; for(var tempNumber of numbers){    if(tempNumber > firstLargerNumber){       secondlargerNumber = firstLargerNumber;       firstLargerNumber = tempNumber;    }    else if(tempNumber > secondlargerNumber){       secondlargerNumber = tempNumber;    } } console.log("The second largest number="+secondlargerNumber);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo138.js.OutputThis will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo138.js The second largest number=80

Trigger a button click and generate alert on form submission in JavaScript

AmitDiwan
Updated on 11-Sep-2020 06:47:17

10K+ Views

Let’s say the following is our button −SubmitOn the basis of button id, on form submission, generate an alert −$("#submitForm").click(function() {    alert("The Form has been Submitted."); });Example Live Demo Document CollegeId= CollegeName=  Submit    $("#submitForm").click(function() {       alert("The Form has been Submitted.");    }); 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 −After clicking the button, you can see the following output −

How to get yesterday’s date in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:45:22

329 Views

To get the yesterday date, first of all get the current date and subtract 1 from the current and use the function setDate(). The syntax is as follows −yourCurrentDateVariableName.setDate(yourCurrentDateVariableName.getDate() - 1);At first, get the current date −var currentDate = new Date();Now, get yesterday’s date with the following code −Examplevar currentDate = new Date(); console.log("The current date="+currentDate); var yesterdayDate = currentDate.setDate(currentDate.getDate()- 1); console.log("The yesterday date ="+new Date(yesterdayDate));To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo137.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo137.js The current date=Fri Jul 31 2020 ... Read More

Generate random characters and numbers in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:43:15

316 Views

At first, set the characters and numbers −var storedCharacters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';To generate randomly, use Math.random(). Following is the code −Examplefunction generateRandom3Characters(size) {    var generatedOutput= '';    var storedCharacters =    '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';    var totalCharacterSize = storedCharacters.length;    for ( var index = 0; index < size; index++ ) {       generatedOutput+=storedCharacters.charAt(Math.floor(Math.random() *       totalCharacterSize));    }    return generatedOutput; } console.log(generateRandom3Characters(3));To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo136.js. This will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo136.js lq4

Assigning values to a computed property in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:41:58

136 Views

Following is our object −const customerDetails=[    {customerFirstName: "David"},    {customerLastName: "Miller"},    {customerCountryName: "US"},    {customerAge: "29"},    {isMarried: false},    {customerCollegeName: null} ];Let’s assign values to a computed property using slice() along with map().Exampleconst customerDetails=[    {customerFirstName: "David"},    {customerLastName: "Miller"},    {customerCountryName: "US"},    {customerAge: "29"},    {isMarried: false},    {customerCollegeName: null} ]; const newCustomerDetails = customerDetails.slice(2, 4).concat(customerDetails[5]).map(obj=>({    propertyKey: Object.keys(obj)[0],    propertyValue: Object.values(obj)[0] })); console.log(newCustomerDetails);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo135.js.OutputThis will produce the following output −PS C:\Users\Amit\JavaScript-code> node demo135.js [    { propertyKey: ... Read More

Get the last item from node list without using length property in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:40:32

307 Views

Let’s say the following is our table − John David Mike Use the following with text() to get last item −$('table tr:last td')Example Live Demo Document John David Mike    var lastValue= $('table tr:last td').text();    console.log("The last value is="+lastValue); 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 −

Assigning function to variable in JavaScript?

AmitDiwan
Updated on 11-Sep-2020 06:37:31

122 Views

Use return statement to assign function to variables. Following is the code −Example Live Demo Document    .demo {       background: skyblue;       height: 20px;       width: 75%;       margin: 10px;       padding: 10px;    } John Smith David Miller Adam Smith    var studentNames = function() {       var names = [];       $(".demo").each(function() {          names.push($(this).data('st'));       });       return names.join();    };    console.log( studentNames() ); 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 −

Fetch value from Alert pop up in jQuery

AmitDiwan
Updated on 11-Sep-2020 06:35:05

443 Views

To fetch value from alert pop up, use alert(). At first, use prompt() to input the value from user. Following is the code −Example Live Demo Document    var value = prompt("Please enter an integer value");    var multiplyBy10=10*value;    alert("Result after multiplying by 10 = "+ multiplyBy10); 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 −Put an integer value and click the OK button.After clicking the OK button, the snapshot is as follows −

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