React js interview questions and Answers

React Router is the in-built routing library for React. React Router helps to keep your UI in sync with the respective URL. It works on a simple API having powerful features like lazy loading, locational transition, and dynamic route matching built right in.

Now, there are two ways to render this object as an array,

First:

render() {
    const data =[{"name":"test1"},{"name":"test2"}];
    const listItems = data.map((d) => <li key={d.name}>{d.name}</li>);

    return (
      <div>
      {listItems }
      </div>
    );
  }

Or, you could directly write the map function in the return

render() {
    const data =[{"name":"test1"},{"name":"test2"}];
    return (
      <div>
      {data.map(function(d, idx){
         return (<li key={idx}>{d.name}</li>)
       })}
      </div>
    );
  }

Note: React is a widely used open-source library used for building interactive user interfaces. It is a web platform licensed under MIT. This is one of the very popular react interview questions.

You can avoid Prop Drilling in the following ways:

• Using a Context API
• Using Render Props

Key Benefits of ReactJS Development

• Allows Developers to Reuse the Components
• It is Much Easier to Learn
• The Benefit of Having JavaScript Library
• SEO Friendly
• It ensures faster rendering
• The Increase in Community Base
• The Support of Handy Tools
• Scope for Testing the Codes etc