When do you need to use refs?

  • To access the DOM node of a component
  • To pass data between sibling components
  • To manage component state
  • To update component props
Refs in React are used to access the DOM node of a component. Refs can be attached to any component, including functional components, and allow developers to access the underlying DOM node or React element. Refs are typically used to access the value of an input or textarea element, or to attach event listeners to a DOM node.

How to combine multiple inline style objects?

  • Using the Array.concat() method
  • Using the Object.assign() method
  • Using the Object.merge() method
  • Using the spread operator
In React, you can combine multiple inline style objects by using the spread operator. This allows you to merge the properties of multiple style objects into a single object that can be applied to a component. For example:

My Component

. This will create a new style object that contains the properties of both style1 and style2.

How to perform automatic redirect after login?

  • Use the "Link" component from React Router
  • Use the "Redirect" component from React Router
  • Use the "history.push" method with the new route
  • Use the "window.location" object with the new URL
In React, you can perform an automatic redirect after login by using the "history.push" method provided by the router. This method adds a new entry to the history stack and navigates to the specified route. You can use this method after successful authentication to redirect the user to a different page, such as a dashboard or a profile page. For example: history.push('/dashboard');.

What is the purpose of eslint plugin for hooks?

  • To enforce best practices for React component development
  • To check for errors in React hooks usage
  • To improve the performance of React hooks
  • To add support for new React features
The eslint-plugin-react-hooks is a plugin for the eslint linter that helps developers avoid common issues with React hooks, such as missing dependencies or incorrect usage. It checks for errors and enforces best practices for using React hooks, which can improve code quality and reduce bugs.

How to create refs?

  • Using the React.createRef method
  • Using the document.getElementById method
  • Using the this.refs object
  • Using the window object
Refs in React can be created using the React.createRef method. This method creates a new ref object, which can be attached to a DOM element or a React component. Refs can be accessed using the current property of the ref object.

Describe data flow in React?

  • Unidirectional data flow
  • Bidirectional data flow
  • Multidirectional data flow
Data flow in React is unidirectional, meaning that data flows in a single direction from the parent component to the child component. This helps ensure that the application state is predictable and easier to manage.

What is React Fiber?

  • A new JavaScript engine developed by Facebook
  • A new component lifecycle method in React
  • A new programming language developed by Facebook
  • A new rendering engine for React
React Fiber is a new rendering engine for React that was introduced in React 16. It is designed to improve performance and enable more flexibility in scheduling updates. With React Fiber, React can break up large updates into smaller chunks, prioritize updates, and pause and resume updates as needed.

What are the limitations of React?

  • Only supports front-end development
  • Poor cross-platform compatibility
  • Poor performance on large datasets
  • Steep learning curve, Limited SEO optimization
React has some limitations, including a steep learning curve and limited SEO optimization. React's focus on component-based architecture can make it more difficult for beginners to learn and understand, and its reliance on JavaScript can make it less friendly to search engines. React can also struggle with performance on large datasets or complex UI components. React is primarily used for front-end development and does not have built-in support for back-end development.

What is context?

  • A JavaScript library for data visualization
  • A global object used to store application state
  • A way to pass data down to child components without using props
  • A way to pass data up to parent components without using props
Context is a way to pass data down to child components without using props. It is useful for data that needs to be accessed by many components at different levels of the component hierarchy. Context provides a way to avoid the "prop drilling" problem, where props need to be passed down through many layers of components.

How to do logging in React Native?

  • Use the console.log() function
  • Use the alert() function
  • Use the debugger statement
  • All of the above
To do logging in React Native, you can use the console.log() function, which writes messages to the console in the same way as in a web browser. You can also use other console functions, such as console.warn() and console.error(), to log warning and error messages.