Found 6710 Articles for Javascript

Set a default value for the argument to cover undefined errors while calling a function in JavaScript

AmitDiwan
Updated on 12-Sep-2020 08:32:21

185 Views

If you won’t pass value to a function(), it will print the default value otherwise given parameter will be printed.Following is the code. We are setting a default here i.e. “Jack” in this case to avoid any undefined error when a function is called without any parameter −Examplefunction display({ name = 'Jack' } = {}) {    console.log(`Hi My Name is ${name}!`); } display(); display({name:"Taylor Swift"});To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo171.js.OutputThis will produce the following output −PS C:\Users\Amit\javascript-code> node demo171.js Hi My Name is Jack! Hi My ... Read More

In JavaScript, can be use a new line in console.log?

AmitDiwan
Updated on 12-Sep-2020 08:29:15

2K+ Views

Yes, we can use a new line using “” in console.log(). Following is the code −Exampleconst studentDetailsObject = new Object() studentDetailsObject.name = 'David' studentDetailsObject.subjectName = 'JavaScript' studentDetailsObject.countryName = 'US' studentDetailsObject.print = function(){    console.log('hello David'); } console.log("studentObject", "", studentDetailsObject);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo170.js.OutputThis will produce the following output −PS C:\Users\Amit\javascript-code> node demo170.js studentObject {    name: 'David',    subjectName: 'JavaScript',    countryName: 'US',    print: [Function] }

Prettify JSON data in textarea input in JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:25:59

10K+ Views

For this, use JSON.parse() along with JSON.stringify().Example Live Demo Document Click The Button To get the Pretty JSON    function printTheJSONInPrettyFormat() {       var badJSON = document.getElementById('prettyJSONFormat').value;       var parseJSON = JSON.parse(badJSON);       var JSONInPrettyFormat = JSON.stringify(parseJSON, undefined, 4);       document.getElementById('prettyJSONFormat').value =       JSONInPrettyFormat;    } To run the above program, just save the file name anyName.html(index.html) and right click on the file and select the option open with live server in VS Code editor.OutputThis will produce ... Read More

Checking a radio in radio group with JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:23:38

577 Views

Let’s say the following is our radio button group −    Gender:    Male    Female To check a radio in radio group, you need to set checked property to true in JavaScript. Following is the code −Example Live Demo Document Gender: Male Female    var tagValues = document.getElementsByTagName('input');    for (const obj of tagValues) {       if (obj.value === 'Male'){          obj.checked = true;       }    } 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 −

How to divide an unknown integer into a given number of even parts using JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:21:07

408 Views

For this, you can use the concept of modular operator along with divide. Following is the code −Examplevar divideInteger = function(value, divide) {    var num;    var modular = value % divide;    if(modular == 0){       num = value/divide;       sumOfDivideParts = Array(divide).fill(num);    } else {       num = (value-modular)/divide;       sumOfDivideParts = Array(divide).fill(num);       for(i=0;i node demo169.js [    6, 6, 6, 6,    6, 6, 7, 7 ]

Display resultant array based on the object’s order determined by the first array in JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:19:31

90 Views

Let’s say the following is our object −var lastName ={    "John":"Smith",    "David":"Miller",    "Bob":"Taylor" }Following is our array −var firstName=[    "Bob",    "John",    "David" ]Display resultant array based on the object’s order determined by the first array, use map(). Following is the code −Examplevar firstName=[    "Bob",    "John",    "David" ] var lastName ={    "John":"Smith",    "David":"Miller",    "Bob":"Taylor" } var values = firstName.map(getValues => lastName[getValues]); console.log(values);To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo168.js. This will produce the following output −PS C:\Users\Amit\javascript-code> node ... Read More

Make first letter of a string uppercase in JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:17:51

431 Views

To make first letter of a string uppercase, use toUpperCase() in JavaScript. With that, we will use charAt(0) since we need to only capitalize the 1st letter.Examplefunction replaceWithTheCapitalLetter(values){    return values.charAt(0).toUpperCase() + values.slice(1); } var word="javascript" console.log(replaceWithTheCapitalLetter(word));To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo167.js.OutputThis will produce the following output −PS C:\Users\Amit\javascript-code> node demo167.js Javascript

How to ignore using variable name as a literal while using push() in JavaScript?

AmitDiwan
Updated on 12-Sep-2020 08:16:41

237 Views

To avoid using variable name as a literal, use square brackets. Following is the code −Examplevar name = "David" var putTheAllData = [] putTheAllData.push( { name: "The name is name will remain same" } ) putTheAllData.push( { [name]: "The name is David will be changed [name]"} ) console.log(putTheAllData);To run the above program, you need to use the following command −node fileName.js.OutputHere, my file name is demo166.js. This will produce the following output −PS C:\Users\Amit\javascript-code> node demo166.js [    { name: 'The name is name will remain same' },    { David: 'The name is David will be changed [name]' } ]

Add object to array in JavaScript if name does not already exist?

AmitDiwan
Updated on 12-Sep-2020 08:12:53

943 Views

For this, use push() along with forEach(). Following is the code −Examplevar details = [{name:"John"},{name:"David"}] var addObject = ["Mike","Sam"]; addObject.forEach( obj1 => {    if(!details.find( obj2 => obj2===obj1 ))       details.push({name:obj1}) }) console.log(details);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo165.js.OutputThis will produce the following output −PS C:\Users\Amit\javascript-code> node demo165.js [    { name: 'John' },    { name: 'David' },    { name: 'Mike' },    { name: 'Sam' } ]

Replace commas with JavaScript Regex?

AmitDiwan
Updated on 12-Sep-2020 08:11:28

675 Views

Let’s say the following are our strings with commas −"My Favorite subject is, " "My Favorite subject is, and teacher name is Adam Smith" "My Favorite subject is, and got the marks 89"To replace commas, use replace and in that, use Regular Expression. Following is the code −Exampleconst makingRegularExpression = /, (?=[^, ]*$)/; replaceComma("My Favorite subject is, "); replaceComma("My Favorite subject is, and teacher name is Adam Smith"); replaceComma("My Favorite subject is, and got the marks 89"); function replaceComma(values){    console.log(values, " ==== replaced by JavaScript ==== ", values.replace(ma    kingRegularExpression, " JavaScript")); }To run the above program, you need ... Read More

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