100+ LWC Interview Questions and Answers

LWC Interview Questions and Answers

We will provide you with a list of questions that you might be asked during an interview for a position at LWC.

LWC Interview Questions and Answers For Freshers

These questions will help you to better understand the job and the company, and will give you a better idea of what to expect during your interview.

So whether you’re looking for your next job, or just want to be prepared for the interview process, read on.

LWC components interview questions

1. What are the two ways to make lightning components?

 

The two ways in which lightning components can be made include :

 

• Aura Components Model
• Lightning Web Components Model

 

2. What is LWC?

 

LWC or Lightning Web Components is a compilation of the latest lightweight frameworks which are based on the current web standards. LWC uses HTML tools and JavaScript to create custom HTML elements. LWC is supported by Salesforce and because of being lightweight, it ensures exceptional performance.

 

3. Why do we need LWC when we have Aura Components?

 

LWC is widely accepted because of its better performance. Transitioning from Aura to LWC can lead to significant and noticeable advantages when it comes to productivity, performance, and portability. Moreover, the distribution of LWC component responsibilities is based on industry standards.

 

4. Why does LWC work faster as compared to Aura Components?

 

LWC does not contain an added abstraction layer and that is why it works faster and more efficiently as compared to the Aura Components. By increasing the speed and security of a platform, LWC, along with increasing the performance rate, also increases deliverability.

 

5. What do you understand by the term ‘Salesforce Lightning’?

 

Salesforce Lightning is a framework that focuses on app development. It works by simplifying the app development procedure for users who have no prior programming experience.

 

6. What is the significance of LWC decorators?

 

Lightning Web Components has 3 decorators. These decorators are important because they add and alter the functionality of a property or function. This means that by adding a decorator, we can add behaviour or characteristics to a specific object.

 

7. What are the different Lifecycle hooks available on LWC?

 

The lifecycle hooks available on LWC include :

 

• Constructor
• Connectedcallback
• Renderedcallback
• Disconnectedcallback
• Error callback

 

8. What is the function of JavaScript in the LWC?

 

JavaScript serves its function in the LWC by defining the behaviour of HTML properties. When a variable, function, or class must be imported, the import statement must be used. In the case of a service component, JavaScript exports functionality to other components.

LWC Interview Questions and Answers in salesforce

9. How would you describe navigation in Lightning?

 

When users want to browse to a reference page or are looking forward to generating a URL from the given page, they can use Lightening; navigation. Some functionalities that can be navigated include Navigation Item Page, Named Page, Record Page, and Knowledge Article.

 

10. Name the different stages of transmission of application events

 

The different stages of transmission of application events include :

 

• Capture Phase
• Bubble Phase
• Default Phase

 

11. What are visual building tools used for?

 

Visual building tools help in quicker and easier app development by providing drag and drop features.

 

12. Mention the different lightning pages types?

 

Lightning pages are available in different types. Some of them are home page, app page, record page and embedded service page.

 

13. Mention the rules you have to follow in naming files?

 

Naming a file comes with certain rules. They are :

 

• The beginning of the File name must be with a lowercase letter

 

• File name must contain only alphanumeric characters or underscore characters

 

• White spaces should not be a part of file name

 

• File name should be unique in the namespace

 

• The file name should not end with an underscore

 

• File name should not contain two back to back underscore characters

 

• Hyphen should not be a part of the file name

 

14. How can you iterate through a list in LWC?

 

LWC provided its users with two ways to iterate through a list. Those two ways are

 

• Use for : each
• iterator

 

15. What is the difference between Lightning Web Components and Aura components?

 

LWC is a collection of tools based on modern web standards. It’s used to create interfaces without the need for JavaScript or the building of a library. It’s a lightweight framework that makes it easier to develop and customise components. On the other hand, Aura components are created with the Salesforce Lightning Component Framework and are built with Salesforce’s proprietary code.

 

16. Which offers better performance? Aura or LWC?

 

LWC offers better performance than Aura components as it is much lighter. LWC also makes debugging a lot easier as it’s built on the latest web standards. Aura components, on the other hand, are not as efficient and can be more difficult to debug.

 

17. What are the advantages of using Lightning Web Components?

 

LWC is incredibly fast. It eliminates the need for additional libraries or frameworks, which means less time spent downloading and loading code. This results in faster page-loads and better user experience.  Another great advantage is that it’s easy to use. You don’t need any special knowledge or experience to get started with LWC.

 

18. Is there any limit to how many Lightning Web Components I can use in an app?

 

The limit to how many LWCs you can use really depends on the complexity of the app you are creating. If you are developing a simple app, then you may be able to get away with using only a few LWCs. However, if you are creating a more complex app, such as an e-commerce site, then you may need to use a larger number of LWCs in order to create the desired functionality.

 

19. How to optimise Lightning Web Components performance?

 

Optimising your Lightning Web Components performance is a great way to ensure that your application runs smoothly and quickly. Here are some tips

 

• Use the latest version of LWC

 

• Use the correct data type

 

• Utilise caching when possible.

 

• Use efficient code

 

• Minimise DOM updates

 

20. Is LWC Secure?

 

LWC is incredibly secure. All of its components are built with security in mind and they’re regularly updated to keep up with the latest security trends. Lwc is an excellent choice for those looking to create sophisticated interfaces without the need for additional libraries or frameworks.

 

21. How can you debug Lightning Web Components?

 

Debugging Lightning Web Components is possible with the right tools and processes in place. Utilising Chrome Developer Tools, built-in debugging tools, loggers, Lightning Inspector, and unit testing are all essential for debugging LWC applications successfully.

 

22. What is the best way to structure my Lightning Web Components?

 

The best way to structure your LWCs is to keep them as modular as possible. This means each component should be responsible for one specific task, and should only contain the code necessary to perform that task. Keeping your components modular makes it easier to maintain and update them when needed.

 

23. Why is unit testing essential in debugging LWC applications?

 

Unit testing is essential for debugging LWC applications, as it allows you to test individual components and ensure that they are functioning correctly.

 

24. What are some disadvantages of LWC?

 

LWC has some cons too. They are :

 

• No two way binding

 

• Doesn’t support LEX console

 

• Use of email templates is restricted.

 

25. Why is lightning process builder used for?

 

Being a tool available in salesforce lightning, it is used to automate processes and to create visualisations.