React Basics - Class 3

Dear Sciaku Learner you are not logged in or not enrolled in this course.

Please Click on login or enroll now button.

If you have any query feel free to chat us!

Happy Coding! Happy Learning!

Lecture 51 :- React Basics - Class 3

In "React Basics - Class 3," we'll continue exploring more advanced React concepts and build on what we learned in the previous classes. We'll cover topics such as React Hooks, forms, and component lifecycle methods.

Let's dive into the new concepts:

Step 1: React Hooks

React Hooks are functions that allow you to use state and other React features in functional components, without the need to use class components. Hooks provide a simpler and more concise way to manage state and side effects in your components.

Here are some commonly used React Hooks:

  • useState: Allows you to add state to functional components.
  • useEffect: Allows you to perform side effects in functional components (e.g., data fetching, subscriptions, etc.).
  • useContext: Allows you to access the nearest context value in functional components.
  • useReducer: Allows you to use a reducer function to manage state in functional components.
  • useCallback and useMemo: Help optimize performance by memoizing functions and values.

Let's rewrite the Counter component from the previous class using useState Hook.

jsxCopy code

import React, { useState } from 'react'; function Counter() {  const [count, setCount] = useState(0);  const incrementCount = () => {    setCount((prevCount) => prevCount + 1);  };  const resetCount = () => {    setCount(0);  };  return (    <div>      <h2>Count: {count}</h2>      <button onClick={incrementCount}>Increment</button>      <button onClick={resetCount}>Reset</button>    </div>  ); } export default Counter;

Step 2: Forms

React makes it easy to handle form inputs and capture user input data. You can use the useState Hook to manage form state and the onChange event to handle user input.

Let's create a simple form component that captures user input and displays it.

jsxCopy code

import React, { useState } from 'react'; function Form() {  const [inputValue, setInputValue] = useState('');  const handleChange = (e) => {    setInputValue(e.target.value);  };  return (    <div>      <input type="text" value={inputValue} onChange={handleChange} />      <p>You typed: {inputValue}</p>    </div>  ); } export default Form;

Step 3: Component Lifecycle Methods

In class components, you have access to component lifecycle methods, such as componentDidMount, componentDidUpdate, and componentWillUnmount. These methods allow you to execute code at different stages of a component's life.

In functional components, you can use the useEffect Hook to achieve the same behavior. useEffect combines the functionality of componentDidMount, componentDidUpdate, and componentWillUnmount.

Let's see how to use useEffect Hook.

jsxCopy code

import React, { useState, useEffect } from 'react'; function Timer() {  const [seconds, setSeconds] = useState(0);  useEffect(() => {    const interval = setInterval(() => {      setSeconds((prevSeconds) => prevSeconds + 1);    }, 1000);    return () => {      clearInterval(interval);    };  }, []);  return (    <div>      <h2>Timer: {seconds} seconds</h2>    </div>  ); } export default Timer;

In this example, the useEffect Hook runs after the component is mounted (similar to componentDidMount). It starts an interval that updates the seconds state every second. Additionally, we've returned a cleanup function from useEffect, which will clear the interval when the component is unmounted (similar to componentWillUnmount).

Step 4: Using Components Together

Now that we've created separate components for React Hooks, forms, and lifecycle methods, let's use them in the App.js.

jsxCopy code

import React from 'react'; import Welcome from './Welcome'; import Counter from './Counter'; import Form from './Form'; import Timer from './Timer'; function App() {  return (    <div>      <h1>Hello, React!</h1>      <Welcome name="React App" />      <Counter />      <Form />      <Timer />    </div>  ); } export default App;

Congratulations! You've completed the third class of React Basics. You've learned about React Hooks, forms, and component lifecycle methods, which are essential concepts in building robust and dynamic React applications.

React is a powerful library that allows you to create highly interactive and scalable user interfaces. As you continue your React journey, you can explore more advanced topics like React context, custom hooks, and state management libraries.

Keep practicing, building more complex applications, and exploring the vast possibilities of React! Happy coding!

13. React Basics

23 Comments

@familyvimes@gmail.com
[email protected] Jul 22, 2024 at 10:33 PM

Kindly check the lecture number 6. Lifecycle of a Change in 1. Git and Github The above lecture is not related to the course please update it ASAP Thank you

@harshp.cs.22
harshp.cs.22 Jul 10, 2024 at 3:37 PM

From where can I download the files which love babbar says he has uploaded on dashboard ??

@familyvimes@gmail.com
[email protected] Jul 23, 2024 at 12:05 PM

I have attached the link https://github.com/lakshayk12/ANN_optimization_BTP

@zubaid.zu
zubaid.zu May 9, 2024 at 2:42 AM

Paid for the course but it still locked, can solve this problem please, when you take the payment the couse should be unlocked, evey time i have to message for any purchase

@admin79
admin79 May 10, 2024 at 10:29 PM

Now your Paypal payment is accepted and your course is activated successfully. Please leave your valuable feedback.

@anandwising
anandwising Mar 12, 2024 at 4:05 PM

Why i am being asked for payment if i am already enrolled in the course

@admin79
admin79 Mar 12, 2024 at 5:22 PM

Dear anand, your payment is now updated check your course, apologize for several delays. Please leave your valuable feedback.

@anandwising
anandwising Mar 12, 2024 at 8:33 PM

thanks its working now

@Megha
Megha Feb 22, 2024 at 11:02 PM

hello ,I have a doubt

@akshaykumrawat99
akshaykumrawat99 Feb 22, 2024 at 10:56 PM

hello i have a doubt

@rajnireddyatr
rajnireddyatr Feb 3, 2024 at 12:08 AM

hi

@talha.developments
talha.developments Jan 18, 2024 at 9:34 PM

I'm paying through my Card, but it giving an error. why ? how we can purchase a course in Pakistan. Paypal is banned here

@aryangrg020
aryangrg020 Jan 17, 2024 at 10:25 PM

can we download the videos

@Krishanpal
Krishanpal Jan 14, 2024 at 8:12 PM

i done my payment for mern stack development love babbar but cant acces to course kindly give me access

@sciaku1
sciaku1 Jan 17, 2024 at 12:28 PM

Dear Krishnapal your payment is already accepted go and check back.

@shivanshgautam220
shivanshgautam220 Jan 10, 2024 at 4:57 PM

Why i am being asked for payment if i am already enrolled in the course

@sciaku1
sciaku1 Jan 11, 2024 at 3:18 PM

Dear Shivansh, if you already done your payment then contact us on our official Email id [email protected] or reply here.

@p8354046
p8354046 Jan 7, 2024 at 3:47 PM

Why i am being asked for payment if i am already enrolled in the course

@sciaku1
sciaku1 Jan 11, 2024 at 3:19 PM

Dear p8354046, if you already done your payment then contact us on our official Email id [email protected] or reply here.

@myidontablet
myidontablet Dec 30, 2023 at 4:28 PM

Why i am being asked for payment if i am already enrolled in the course

@sciaku1
sciaku1 Jan 6, 2024 at 1:42 AM

Dear, Don't worry now your problem is solved check your id.

@duabhi911
duabhi911 Nov 16, 2023 at 2:03 AM

Why i am being asked for payment if i am already enrolled in the course

@harshp.cs.22
harshp.cs.22 Dec 23, 2023 at 11:40 AM

Yes bro

@myidontablet
myidontablet Dec 30, 2023 at 4:28 PM

I'm facing same issue

@sciaku1
sciaku1 Jan 6, 2024 at 1:43 AM

Dear, Don't worry now your problem is solved check your id.

@lenientharsh
lenientharsh Oct 31, 2023 at 10:56 AM

i want debit card option

@lenientharsh
lenientharsh Oct 31, 2023 at 10:51 AM

how can i assure that this is not scam?

@jainarin416
jainarin416 Nov 2, 2023 at 12:37 AM

i have same doubt is this website real or a fraud

@sciaku1
sciaku1 Jan 6, 2024 at 1:45 AM

No its not any fraud. its genuine if you need any proof please contact us via email.

@sciaku1
sciaku1 Jan 6, 2024 at 1:44 AM

No it's not any scam, its genuine if you need any proof please contact us via email.

@hydrarishabh9
hydrarishabh9 Oct 21, 2023 at 11:47 PM

how to do payment ?

@sciaku1
sciaku1 Oct 30, 2023 at 5:34 PM

Click on Watch now button then click next video then payment option is showing

@minhajakram440
minhajakram440 Oct 18, 2023 at 11:18 PM

i am unable to access the video even i have already completed my payment .

@aeromusgyan
aeromusgyan Oct 21, 2023 at 1:17 AM

Your problem is solved

@saklyi70
saklyi70 Sep 30, 2023 at 11:02 AM

plz add codes lecture wise ! it wold be great and helpful also

@sciaku1
sciaku1 Jan 6, 2024 at 1:47 AM

now we have added starter package in lecture 2nd, go now and download it.

@thomasroka31
thomasroka31 Sep 29, 2023 at 4:05 PM

how to view this one

@jitendrakrverma02
jitendrakrverma02 Sep 23, 2023 at 3:57 PM

Why video not play

@sciaku1
sciaku1 Jan 6, 2024 at 1:47 AM

Now it's working.

@9035praveen
9035praveen Sep 2, 2023 at 12:12 PM

Thank you for the access of the videos. It would be greatful if I could no the way to download the videos

@mohammedunaismdr
mohammedunaismdr Sep 25, 2023 at 11:54 AM

Use idm to download

@mishraprajjwal295
mishraprajjwal295 Oct 13, 2023 at 11:07 PM

ok

@rahulkumarbaraswal30
rahulkumarbaraswal30 Nov 4, 2023 at 1:32 PM

Hello bro can you share course with me?

@bicky
bicky Sep 1, 2023 at 5:42 PM

hello everyone

Frequently Asked Questions About Sciaku Courses & Services

Quick answers to common questions about our courses, quizzes, and learning platform

Didn't find what you're looking for?

help_center Contact Support