Monday, September 27, 2021

Top 25 Vue.js Interview Questions and Answers for 1 to 2 Years Experienced

Hello guys, if you are preparing for Vue.js interviews and looking for some frequently asked Vue.js questions from interviews then you have come to the correct place. Earlier, I have shared React.js Interview questions and JavaScript questions and in this article, I am going to share common Vue.js Interview questions for 1 to 2 years experienced web developers. With the success of libraries like React.js, developers around the globe are leaning more towards such flexible technologies. Though full-fledged frameworks like Angular are also popular and widely used, developers want flexibility.

React.js is known for its flexibility. The popularity of React gave birth to another JavaScript library or framework (depending on your goal), called Vue.js. Created by Evan You in the year 2014, Vue had a modest start. It did not catch the attention of many developers. But in the past few years, Vue's popularity has increased immensely. 

Vue's popularity exceeded React as well as Angular on GitHub by a fair margin. Also, the states on the NPM registry prove that Vue.js is becoming more popular than React and Angular.

Vue.js is a progressive JavaScript framework and many consider it as a powerful and high-performing alternative to Angular. It has taken some of the best features from React and Angular. Moreover, Vue.js is simpler. It's easy to use. In recent years, Vue has become a perfect choice for developers. 

However, it's still gaining popularity. But in the future, it is definitely going to become a top choice for web developers. Some even believe Vue will replace the likes of React and Angular.




 

20+ Vue.js Interview Questions with Answers

Vue is fairly new. You will not find many people with experience in Vue.js interviews. But we will list 25 frequently asked Vue and Vuex interview questions in this article that will help you clear the interviews. These questions will revolve around the most important topics of the library.

 

1. Tell us something about Vue.js?

A: Vue.js is a progressive JavaScript web framework. It is used to build single-page applications and dynamic user interfaces.

 

2. What are the different methods of installing Vue?

A: The simplest method of installing Vue.js is by using the Node Package Manager (NPM). Other ways are: 1) Using Bower 2) Using Vue-CLI 3) Using CDN.

 

3. How will you handle APIs in Vue.js?

A: Several third-party libraries could be used for handling APIs in Vue. But the best and most used library is Axios. It is lightweight and easy to use.

 





4. Can you explain Vue-resource?

A: Vue-resource is a plug-in that could be used in Vue to handle web requests and responses.

 

5. How to create an instance in Vue? Can you write code for it?

A: An instance in Vue can be created using the Vue function.

var v = new Vue({})

 

6. Why should we use Vue.js?

A: We should use Vue.js because it has many features.

1. Vue.js is extremely flexible.

2. It is easy to use.

3. It is small in size.

4. It can be integrated easily with existing applications.

5. It uses virtual DOM that enhances the performance.

 

7. What are component props in Vue.js?

A: In Vue.js, it is not possible to reference parent data directly into the child component's template. It happens because every component instance in Vue has an isolated scope. So to pass the data from parent to child components, Vue uses component props. So basically, props are customized attributes that are passed from the parent component to the child component.

 

8. Explain Vuex.

A: Vuex is a pattern plus library used for state management in Vue.js. It is used to centralize the state of the application in a single place called the store.

Top 20  Vue.js interview Questions and Answers for 1 to 2 Years Experienced


 

9. Name some of the commonly used directives in Vue.js.

A: v-show, v-model, v-if, v-else, v-on

 

10. What is the use of the v-show directive?

A: It is used to render all the elements to the DOM. Then it uses the display property of CSS to show or hide the elements according to the instructions.

 

11. What is the use of the v-if directive?

A: It is used to render the elements to the DOM. But it only happens if the expression provided is true. It works like the if the statement of the programming languages.

 

12. Explain lifecycle hooks.

A: Whenever an instance in Vue is created, it goes through different phases like mounting and destroying. In all these phases, different functions are triggered at specific timings. These functions are called lifecycle hooks.

 

13. Name all the lifecycle hooks in Vue.js.

A: beforeCreate, created, beforeMount, mounted, beforeUpdate, updated, beforeDestroy.

 

14. Explain beforeUpdate hook.

A: The beforeupdate hook is triggered just before the data of a component changes and before an update cycle begins. Moreover, it runs before the DOM is re-rendered.




 

15. Which lifecycle hook is executed after the data changes in the component?

A: the updated hook is executed after the data changes in the component.

 

16. Explain virtual DOM?

A: Virtual DOM is a lightweight copy of the original DOM. Instead of directly updating the original, Vue.js first updates the Virtual DOM, and then the real DOM is changed. This enhances the performance of the application.

 

17. What is one-way data flow in Vue.js?

A: In Vue.js, data flows from the parent component to the child component through props. These props are custom attributes that are received as properties by the child component. This is called one-way data flow.

 

18. List all the types of directives in Vue.js?

A: The different types of directives in Vue.js are: General, Empty, Custom, and Literal.

 

19. Why use Mixins in Vue.js?

A: Mixins have many benefits.

1. Mixins help in code reusability.

2. They provide flexibility.

3. They do not affect changes that are outside their scope.

 

20. What is the usage of $parent and $child properties in Vue.js?

A: With the $parent property, we can access the instance of the parent component from a child component. Similarly, with the $child property.

 

21. What is the meaning of a single-file component in Vue.js?

A: A file with .vue extension that contains the Vue component with its template, styles, and logics bundled together is called a single-file component.

 

22. How to avoid memory leaks in Vue.js? What is the main reason for memory leaks in Vue?

A: Memory leaks could be avoided in Vue.js by using the beforeDestroy() lifecycle hooks. The cleanup should be done manually using this hook.

One of the main reasons for memory leaks in Vue is the incorporation of third-party libraries.

 

23. Why is Vuex preferred over Redux with Vue for.js for state management?

A: Following are the reasons why Vuex is preferred over Redux for state management in Vue:

1. Mutations in Vuex are easier to work with than Reducers in Redux.

2. Vuex has better dev tools.

3. Vuex is easier to set up.

4. Beginners can understand Vuex easily.

5. Asynchronous in Veux is organized better.

6. Overall, Veux is easier to use than Redux.

 

24. How Vuex is different from Redux?

A: Though both of them are inspired by Flux, Veux does not make the state immutable like Redux. Instead, it mutates the state. Moreover, unlike Redux, Vuex does not have reducers. It uses Mutations.



That's all about the popular Vue.js interview questions for 1 to 2 years experienced web developers. Vue.js is not a huge framework. It is considered a small framework. So we tried our best and took out the questions that are commonly asked in a Vue.js interview. Go through the questions and try to pick out the topics according to which these questions are made. Research around them and you will find yourself ready for a Vue.js interview.

 Other Fullstack Web development articles you may like to explore


Thanks for reading this article so far. If you like these common Vue.js or Vuex interview questions and answers, then please share them with your friends and colleagues. IF you have any questions or feedback, then please drop a note.

P. S. - If you are new to Vue.js and don't mind learning from free resources like free online courses, books, and tutorials then you can also check out this list of 10 Free Vue.js Courses for Beginners in which I have shared some useful free resources for web developers to learn Vue.js in 2021.

No comments :

Post a Comment