Q: How do you optimize the performance of an LWC component?
A: You can optimize performance by minimizing re-renders, using @wire efficiently, leveraging caching, avoiding deep nested components, and using lightning-emp-api for real-time updates.
Q: How do you implement custom navigation in LWC?
A: Custom navigation can be implemented using the NavigationMixin from lightning/navigation, allowing you to navigate to records, objects, external URLs, or custom pages.
Q: How do you manage complex state in LWC?
A: Complex state can be managed using a state management pattern like Redux, or by creating a service layer that handles state and provides reactive data to components.
Q: How do you implement dynamic component loading in LWC?
A: Dynamic component loading can be achieved using import() for lazy loading modules and conditionally rendering components based on user actions or data.
Q: How do you handle bulk data processing in LWC?
A: Bulk data processing can be handled by implementing batch Apex or using asynchronous Apex methods, and then exposing results to LWC via wire services or imperative calls.
Q: How do you implement internationalization (i18n) in LWC?
A: Internationalization is implemented by using custom labels for static text and Intl API for date, time, and number formatting, along with locale-specific resource bundles.
Q: How do you handle real-time updates in LWC?
A: Real-time updates can be handled using the lightning-emp-api to subscribe to Platform Events or Change Data Capture events, and updating the UI accordingly.
Q: How do you handle client-side caching in LWC?
A: Client-side caching can be implemented using the Cache API, storing frequently accessed data in localStorage or sessionStorage, and managing cache invalidation strategies.
Q: How do you manage component dependencies in LWC?
A: Component dependencies are managed by ensuring proper encapsulation, using @wire for data dependencies, and leveraging event propagation or Lightning Message Service (LMS) for inter-component communication.
Q: How do you handle complex form validation in LWC?
A: Complex form validation is handled by using custom validation logic in JavaScript, integrating third-party validation libraries, and leveraging the reportValidity method on input components.
Q: How do you implement custom events with payloads in LWC?
A: Custom events with payloads are implemented by creating CustomEvent instances, passing data through the detail property, and dispatching the event.
Q: How do you manage multiple API callouts in LWC?
A: Multiple API callouts are managed using Promise.all to handle parallel asynchronous operations, or using async/await for sequential processing.
Q: How do you implement role-based access control (RBAC) in LWC?
A: RBAC is implemented by querying user roles and permissions in Apex, and conditionally rendering components or features based on the user’s role.
Q: How do you handle data normalization in LWC?
A: Data normalization is handled by transforming raw data into a consistent format using JavaScript utility functions or by processing data in Apex before passing it to LWC.
Q: How do you implement server-side rendering (SSR) in LWC?
A: Server-side rendering is not natively supported in LWC, but similar effects can be achieved by prefetching data server-side and passing it to LWC components via lightning-record-page.
Q: How do you create a custom file upload component in LWC?
A: A custom file upload component can be created using standard HTML file input elements, handling file selection in JavaScript, and uploading files via Apex methods.
Q: How do you handle pagination with infinite scroll in LWC?
A: Infinite scroll pagination is handled by detecting scroll events, checking proximity to the bottom of the list, and loading additional data as needed.
Q: How do you implement a wizard-like interface in LWC?
A: A wizard-like interface is implemented by creating a series of steps using lightning-progress-indicator and lightning-button components, managing state transitions between steps.
Q: How do you handle data binding with complex objects in LWC?
A: Data binding with complex objects is managed by ensuring that nested properties are reactive, using @track or @api decorators, and updating the object references correctly.
Q: How do you implement drag-and-drop functionality in LWC?
A: Drag-and-drop functionality is implemented using standard HTML5 Drag and Drop API, handling drag events in JavaScript, and updating the component state accordingly.
Q: How do you use Apex continuations in LWC?
A: Apex continuations are used for long-running callouts, with the continuation object in Apex handling the callout and the LWC component processing the response asynchronously.
Q: How do you handle large file uploads in LWC?
A: Large file uploads are handled by chunking the file into smaller parts client-side, uploading each part via Apex, and reassembling the file server-side.
Q: How do you implement offline capabilities in LWC?
A: Offline capabilities are implemented using the service worker API, caching necessary resources, and handling data synchronization when back online.
Q: How do you manage state in parent-child component relationships in LWC?
A: State in parent-child relationships is managed by passing data via @api properties, using custom events for communication, and leveraging slots for flexible content distribution.
Q: How do you optimize rendering performance in large LWC lists?
A: Rendering performance in large lists is optimized by using virtualization techniques like lazy loading visible items, and avoiding unnecessary re-renders by managing state updates efficiently.
Q: How do you implement secure data handling in LWC?
A: Secure data handling is implemented by ensuring proper field-level security, using Apex for sensitive operations, and validating all inputs client-side and server-side.
Q: How do you handle session management in LWC?
A: Session management is handled by leveraging Salesforce session cookies, implementing session timeout logic in JavaScript, and using refresh tokens for re-authentication.
Q: How do you implement a custom modal component in LWC?
A: A custom modal component is implemented using standard HTML/CSS for the modal structure and JavaScript to handle opening, closing, and backdrop interactions.
Q: How do you handle dynamic component updates based on user interactions in LWC?
A: Dynamic updates are handled by using reactive properties, JavaScript event listeners, and conditional rendering based on the component state.
Q: How do you integrate Salesforce DX with LWC development?
A: Salesforce DX is integrated by using the Salesforce CLI for project setup, version control for source tracking, and CI/CD pipelines for automated deployments.
LWC Interview Questions and Answers
LWC Interview Questions and Answers – Part 1
LWC Interview Questions and Answers – Part 2
LWC Interview Questions and Answers – Part 3
LWC Interview Questions and Answers – Part 4