Total 20 question (100 marks)
- 1. What is the default local host port that a React development server uses?
- 2. To develop and run React code, Node.js is required.
- 3. React can only render elements in the root document element.
- 4. What type of element will be rendered from the following code? function Hello() { return <h1>Hello reactjs</h1>; } ReactDOM.render(<Hello />, document.getElementById('root'));
- 5. If you want to import just the Component from the React library, what syntax do you use?
- 6. What is the smallest building block of ReactJS?
- 7. At the highest level, React components have lifecycle events that fall into.
- 8. What is the children prop?
- 9. What happens when the following render() method executes? render(){ let langs = ["Ruby","ES6","Scala"] return (<div>
- 10. In JSX most of the errors can be caught during _________.
- 11. React keeps track of what items have changed, been added, or been removed from a list using ________.
- 12. Invoked once, only on the client, after rendering occurs.
- 13. When rendering a list using the JavaScript map() method, what is required for each element rendered?
- 14. React separates the user interface into components. How are components combined to create a user interface?
- 15. What tool does React use to compile JSX?
- 16. props in react can________.
- 17. JSX is faster because it performs ____________ while compiling code to JavaScript
- 18. How can you optimze performance for a function component that always renders the same way?
- 19. What command is used to start the React local development server?
- 20. How can we prevent default behavior in React? What method you can call?