Differences between Javascript object constructor and object literal

Similar Questions:
Creating Objects - New Object or Object Literal Notation?
Literal Notation VS. Constructor to Create Objects in JavaScript

As I embark on my initial Javascript tutorial journey, I have come across two distinct methods of creating a JS object.

var person = new Object();
person.name = "Tom";
person.age = "17";

and

var person = {};
person.name = "Tom";
person.age = "17"

Is there any dissimilarity between these two approaches to object creation? Given that the second method seems more straightforward, can it be used universally under all circumstances?

Answer №1

Not only is the second format easier to understand and guaranteed to work in any scenario, but the first format may not be reliable under certain conditions:

function Object() {
    // Oops, we've overridden the Object function!
    return [];    // returning an array just to mess with you
}

var person = new Object();   // not what you expect it to be

However, using {} as a syntactic construct makes it immune to such deceptive tactics.

Moreover, the object literal notation can be optimized partially during parsing, since there's only one type of object that could be created. This could result in a slight performance boost.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

If a second instance is hidden, SVG will appear as a mysterious black box

Two separate div elements each contain an identical SVG graphic. If I hide the first div by setting it to "display: none", the SVG in the second div appears as a gray box. This issue is present in both Firefox and Chrome browsers. Any insights into why ...

Revisiting the Issue: Jquery Hover Effect Fails to Function in Internet Explorer

Can anyone provide assistance with this issue? The code snippet works perfectly in all browsers except for IE, where the menu does not fade in and looks unattractive. html <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.o ...

Is it possible to implement a while loop in React?

Issue: I am facing a challenge while attempting to generate an array of 4 elements from a list using a while loop, but it seems to result in an infinite loop. const [options, setOptions] = useState([]); const fetchElements = () => { while(options. ...

Switching from the jQuery .it() function to the Angular framework

I am looking to convert this code to Angular. I have already written some of the code, but I am unsure what to use in place of :It(). The jQuery code can be found at the following URL: jsfiddle.net Here is my Angular code: x = 3; $scope.itemsPerPage = 3; ...

There is no information stored in req.session.passport, and req.user is not defined

I've previously raised a similar issue, but it was under the Javascript category. I now have more specific insights into what might be causing the problem. The main issue is that req.session.passport appears empty in my logs. As I navigate through my ...

Unable to transfer bootstrap form data from the view to the controller due to issues with bootstrap validations

Scenario I have integrated a bootstrap form into my codeigniter application with bootstrap validation to ensure data accuracy. I want the submit button to work properly so that users can successfully submit the form and be redirected to the action page ...

The CSS navigation bar is not properly aligned in the center

This menu was constructed by me: JSBIN EDIT ; JSBIN DEMO Upon closer inspection, it appears that the menu is not centered in the middle of the bar; rather, it is centered higher up. My goal is to have it positioned lower, right in the middle. I ...

Retrieve data from HTML Form arrays using JavaScript

I have a situation in my forms where arrays are being sent back in the following format: <input class="checkbox-service" name="services['electricity']" type="checkbox"> <input class="checkbox-service" name="services['water'] ...

Problems arise when JQuery fails to function properly alongside ajax page loading

While utilizing ajax to load the page, I encountered an issue where the jQuery on the loaded page template was not functioning until the page was manually refreshed. The ready function being used is: jQuery(document).ready(function() { jQuery(' ...

Uploaded images from mobile devices appear to be rotated when viewed on desktop browsers like Chrome and Firefox

I'm facing a strange issue where an image uploaded from a mobile device to my website appears rotated on Chrome and Firefox when viewed on a desktop. However, it displays correctly on mobile browsers like Chrome Mobile and Safari Mobile. It seems tha ...

Warning message regarding unhandled promise rejection in NestJS websockets

I've encountered a puzzling issue while attempting to integrate an 'events' module into my application to utilize websockets. Upon adding the module, an unexpected error surfaced: (node:59905) UnhandledPromiseRejectionWarning: Unhandled pro ...

Issue encountered while serializing data in next.js when utilizing getServerSideProps function

Encountering An Error Error: The error message "Error serializing .myBlogs returned from getServerSideProps in "/blog"" keeps popping up. I'm facing a problem while attempting to log the data! Initially, when I was fetching data using use ...

Setting up camera in ThreeJS

I am brand new to ThreeJS and currently trying to incorporate it into my web application. I have encountered a problem with configuring the camera. Currently, I have a perspective camera that is able to look at and move in every direction within my scene. ...

Rails MultiSelect Array not converting to String Correctly

I am having trouble converting my array to a string properly. I am using rails multiselect: Views: <%= f.select :foo, [ ['a'], ['b'], ['c'] ], {:prompt => "Select an alpha"}, {:multiple => true} %> Controller: ...

Retrieving the value of an inner div upon clicking the outer div

I currently have a collection of button divs, each containing distinct information: <div class="button"> <div id="first"> Johny </div> <div id="second"> Dog </div> <div id="third"> Pasta & ...

What is the best way to handle code versioning using Django, Angular2, and Webpack?

Currently, I am utilizing Django in conjunction with Angular 2 and Webpack. Within Django, I have set up a URL to display my application at http://example.com/user/beta. Initially, my index.html file is rendered, which contains my Angular 2 components. Wit ...

Modify input value using jQuery upon moving to the next step

When you type into an input[text] and press the tab button, it automatically moves to the next input. If you fill out all the inputs and then want to re-fill them, the values will be highlighted in blue. However, I wanted to achieve this without having to ...

Dealing with submit errors in React Redux forms

I am facing a challenge with handling exceptions properly when submitting in redux forms. I want to display a toast message when an error occurs. LogIn.js: class LogIn extends PureComponent { onSubmit = (values) => { const { login } = this.props; ...

Understanding the concept of for loops in JavaScript and incorporating them in CSS styling

Hello there! I initially used this code to draw 12 lines, but now I am looking to incorporate a for loop and implement it in CSS. Can someone please guide me on how to proceed? <!DOCTYPE html> <html> <head> <style> #straigh ...

Step-by-step guide on implementing a fade effect to a specific JavaScript element ID

When I click a button, the image on the screen disappears. I am looking to add a fade effect to this action. Can someone help me achieve this using CSS? #hide{-webkit-transition: all 1s ease-in-out;} For reference, here is a demo showcasing the current b ...