With the growth in the adoption of React Js, there are also concerns from users, enthusiasts, and even hobbyists. That’s why we’ll be answering seven of the most pressing questions about React Js.
These seven questions about React Js were selected from search engines, forums, and even social media. Whether you are preparing for a React Js interview or a React Js developer, these questions will rest your worries about React Js.
We’ll provide answers to both technical and non-techy questions you might have.
1. Why Should Anyone use React Js?
There are several reasons why everyone is tilting toward React Js. As a point of entry, the ability of React Js to improve the performance of applications will continue to be a significant reason why it’s a preferred choice among developers.
From another perspective, React Js is loved due to code readability; this is due to its reliance on JSX. React Js has no issues syncing with Angular, Meteor, and other frameworks from the integration angle.
These are just a few of the reasons why many people love React Js.
2. How Does Virtual DOM Works in React?
React creates virtual DOM. Anytime a state changes in the component, a “diffing” algorithm is run to identify whatever has changed in the virtual DOM. There comes the reconciliation, which updates the DOM with whatever the “diff” comes up with.
Remember HTML DOM? Virtual DOM is an abstract form of HTML DOM. Albeit lightweight and detached from browser-specific implementation rules. In simple terms, a change in the React Component is always identified and updated.
What is different is that the update in Virtual DOM is faster than what is obtainable in a regular DOM.
3. What is “StrictMode” component, and why should Anyone use it?
There is always the need to provide additional visibility. That’s the function of StrictMode as a component included in React. Whenever this application runs in development mode, they logged into the development console when issues arise.
However, these issues are not reflected if the application is running in production mode.
There’s also another usage of StrictMode exploited by developers, and it’s to locate problems. More importantly, ensuring that the React component follows best practices.
4. What are the Common Styling Approaches in React Js?
There are four common styling approaches; CSS Classes, Inline CSS, Pre-processors, and CSS-in-JS Modules.
When developers use React Js for the first time, they often resort to CSS for their styling. This is due to the familiarity with the approach. Afterward, you see them graduating to Inline CSS, which requires the element to be wholly scoped.
Another common styling approach involves the use of pre-processors like Sass, Stylus, and Less. There’s also CSS-in-JS modules such as Emotion, Styled Components, and styled-jsx.
5. How Would You Investigate and Fix a React Application rendering a Page Slowly?
The first step towards fixing a slow page in a React app will be to deploy a profiler app from the React developer tools plugin. With the profiler app, you’ll be able to pinpoint whichever component is taking forever to render or rendering too frequently.
Look out for components re-rendering unnecessarily, as it’s a common issue within React applications.
You can deploy the React.memo and PureComponent tool to prevent re-rendering of function and class components, respectively. In the end, measure the before and after performance of the components after using the tools.
6. Why Should Anyone Use React Hooks?
Simply put. React Hooks allow for easy manipulation of the functional components without a need for converting into class components. Talking generally, hooks enable the extraction and re-utilization of the stateful logic across multiple components.
All of this occurs without a burden on the higher-order components or render props.
However, hooks do not function within classes.
7. How Can Prop Drilling Be Avoided When Building a React Application?
There is often the need for deeply nested components to use data provided by components higher in the hierarchy. The approach is to pass a prop from each component, which is next in hierarchy; this is refer to as prop drilling.
Which this might appear as a necessity; prop drilling comes with its cons. Some components should not feel the data, but they become aware of it, which complicates issues.
The standard way to avoid prop drilling will be to use React context. With this, the component that supplies data become defined. For instance, the component that utilizes data does so via a consumer component or a usecontext hook.
All of this questions have become pertinent with the increase in the popularity of React Js.