Swetha Dhandu

Hi, team. I have 4.7 years of experience in your development using Yeah. Apprenders tag like React, JavaScript, HTML, CSS, Redux, and had a great experience in writing test cases using Jest's time-effecting library. And I pursued my graduation from JND College of Engineering with a degree in CDPA, and that was a college topper in intermediate with 97.5%, and I started my career with DCS in June 2019. Later, I joined EPAM systems in March 2022.

What steps do you follow to refactor a large component into smaller, more manageable components in React? Yeah. Can re-pattern a larger component, or a larger application's larger components into smaller ones by following a clean code methodology. In clean code, it should not have more than 200 lines of code per component. And we can follow SOLID principles also to maintain large components into small components. For refactoring, what it says is, we have to write a component or function with a single responsibility. If you're adding a function, its action should depend on only one responsibility. The function should do only one action. If we divide the code into small functions, we can try a component with the useful functions that are really useful in that component. Or else, we can write some helper components, which if we need complex JavaScript functionalities, we can write a helper file, and we can import them into our component. This can also divide larger components into smaller ones. And, in SOLID principles, we can use interface aggregation and dependency inversion. Those principles we can use for refactoring large components into small components. Based on that, without affecting the code logic, we can improve the React application performance also by refactoring.

Your approach to creating a controlled form in React that handles both validation and submission. In React, we can control forms by having handlers. Handlers in form. Actually, we have some events that will act by default. For example, in a form, we can see the submit action. It will take place by default. We can prevent that by using a synthetic event like preventDefault. By using that, we can prevent the default submission of the form. And we can take control of submission in a user-defined handler. For example, on the submit of a form, whatever I want to do, I can define by writing a submit handler and assign that submit handler to the on submit event of the form. So that I can control the submission of the React form. And for validation, what we can do is for every input that we are taking from the form, we can validate by using handlers. For example, I'm taking one input and I'm expecting an email ID from the user through that input. For that, what I have to do is write an on change email handler for that input and in that handler, I have to mention all the validation rules, like what should be in the email ID, what should not, and how the format will be, and how the regular type of that one. That everything I have to specify in that event handler of on change for the input event. And if there is anything missing from the rules, we can specify it as an error, like if the email ID is not matching the requirements, we can specify that in the error. And we can update that error state and we can show that in the UI. Like that, you can handle forms.

You choose to use Redux Tank or Redux Saga for asynchronous actions in a Redux application. Redux Toolkit is used mainly for complex React applications and where we want to integrate middleware for React and Redux to integrate React and Redux. We need a middleware whenever we need that, so we'll go with Redux Toolkit. I've had a good experience with React, and I didn't get a chance to work with Redux Saga. In Redux, it allows developers to write nested actions inside the action files and integrate them, passing those actions into the reducers to update the Redux store based on the actions and they are dispatched through the user, so that we can use Redux.

To ensure API calls are made efficiently in a React application, we take an approach to avoid unnecessary network requests. We use promises to call API calls instead of synchronous or blocking methods. This allows for more insights into the React application's behavior when making API calls. Prometheus can provide further insights into the application's performance, including the number of necessary network requests made. Along with the HTML request body, we include a payload and necessary information for making API calls. We use the Axios library to make API calls, which provides a convenient and efficient way to handle HTTP requests in React applications.

To set up unit testing for a React application, you would use the React Testing Library. Here's the corrected transcript: How do you set up unit testing for a React application? What libraries would you use? Yeah, to write unit tests for a React application, we have to use, or rather, we can use just an engine or the React Testing Library. Also, we can use Jest. We have to install the React Testing Library, or else we can install Jest. Then, inside Jest, we have three functions: render, shallow, and mount. We're using these three types. We can write test cases. Shallow is for the actual component only. We can use it to write unit test cases without digging deep into the child components. If you want to dig deep into the components and render the props also for writing unit test cases, we have to use mount. Render is also for the rendered part only, but it cannot access the just functions like the ones out of the rendering part. To test the rendering part alone, we can use the render methods from the React Testing Library.

Following React codes, not updating the state correctly. When increment count is called, common security issues arise. In a short time, I'll explain how this might lead to unexpected results and propose a solution. Commenter: Time. Actually, I have a colleague with functional components only. In my experience, I didn't get a chance to work with class components. They start to state, not counter and updating state using this. I'm not clear on how to check and what is there. If it is a functional component, I'll definitely solve it. Sorry about that.

Even this time the script snippet is in React or this and the potential pitfalls and provide information. Interface name, string, age number, Send out a person. Okay. Here, we take an interface, Type person and having 2 parameters, name and age. And we are calling the display person method of type, Display personal. Okay. And having a proper person of type, person interface, that is fine. Here we are taking 1 person constant and we didn't mention any type of that person, and it will throw an error when calling this constant. For this constant, we didn't define any type, and inside that, we have some variables, properties like name, age, email. For them also, we didn't define any type. If we define this person of Type person interface, then it will also throw an error because the person interface has name and age properties only. And the person object has name, age, email. To solve this, we have to add an email property to the person interface and assign that person type to the given object person, or else we can override the person interface with an email object and then we can assign the person interface as a type to the person object.

All considerations they take into account when implementing a scalable Redux architecture. By implementing Redux architecture, we have to check whether the given application really needs Redux or not because when we are going to use Redux, the React application has complex state data to manage. And only then we have to go with the Redux approach. We can use the context API or simple state management. Then, for expanding scalability. We have, in Redux, we must have reducers, action creators, and a store, which is created by using create store. In Redux, we use state and actions. And in actions, we have a type and a payload. To maintain the Redux store as scalable, we should have readability. Like, we should have each and everything as separate files for reducers, separate files for actions, and separate files for the store. And while each action should be defined clearly with its type and payload, and each reducer should be defined with each state and action. Then we can combine all those reducers using combineReducers and send that to the store.

Server side rendering in React applications benefits the initial rendering of the application takes place on the server side, then it returns HTML to the view layer for display purposes. We use this approach by using Next.js, one of the frameworks we can use in React applications to enable server side rendering. It improves the search engine optimization and performance of the application as we are rendering the application initially on the server side. This leads to improved search engine optimization and increased performance of the application.