Jan 15, 2019

10 jQuery Interview Questions You Need to Know

jQuery is a lightweight JavaScript library that makes it easier to use JavaScript on a website. If you're applying for a job as a front-end web developer or similar position, your interviewer might test your knowledge on using jQuery. While they're not likely to go in depth into the subject, there are a few jQuery interview questions that you should be prepared to answer.

1. What is the difference between jQuery and JavaScript?

JavaScript is a programming language, and jQuery is not. jQuery is a library written in JavaScript code designed to simplify several tasks by allowing you to write less code.

2. What are some things that can be done using jQuery?

One of jQuery's top features is that it supports the efficient implementation of AJAX applications. It is also capable of event handling, applying or changing CSS, DOM manipulation, built-in animations, and cross-browser support.

3. What are some advantages of jQuery?

In addition to its main features and capabilities, jQuery has a number of advantages. It's easy to use and learn, easy to expand, has a large pool of built-in methods, and numerous plugins.

4. What is the difference between size and length in jQuery?

Size and length both do the same thing, which is to return the number of elements in an object. However, length is preferred over size because it is faster. Length is a property whereas size is a method.

5. What is the difference between .js and .min.js?

There are two different versions of a jQuery library: development and deployment. Both are the same as far as functionality is concerned, but deployment is a much smaller version of the library file. The .min.js refers to the deployment version that loads faster than .js due to being about 50 percent smaller.

6. What are .empty(), .remove(), and .detach()?

The .empty() method removes all of the child elements from a matched element. The .remove() method removes all of the matched elements and all of the jQuery data associated with them. The .detach() method removes all of the matched elements but leaves the jQuery data intact.

7. What is the dollar sign in jQuery and how is it used?

The dollar sign is an alias or shorthand for jQuery. Rather than typing out the full name, you can simply use a dollar sign symbol. If you're using a JavaScript library that already has a dollar sign in use, you can either use jQuery.noConflict() to delegate another symbol or type out the name.

8. What is jQuery connect and how is it used?

jQuery connect is a plug-in that binds one function with another. Before using the connect function, you have to download the file and include it in the HTML file. You'll then use jQuery.connect to bind two functions together.

The Dough cookie plug-in is an easy way to create, read, or delete cookies in jQuery.

10. What is a CDN and what are the two types?

CDN stands for Content Delivery Network and refers to a collection of servers around the world in which a request goes to the closest one. The two types of CDNs are Google and Microsoft. Google loads jQuery from Google libraries API and Microsoft loads jQuery from AJAX CDN.

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