ReactJS? ?? ??? ????? ??? ?? ???? ?? ?? JavaScript ????????. ??? ??????? ???? ?? ?? ???? ????? ?? ?? ??? ????? ???? ???? ??? ???? ?? ??????. ??? ???? ?? ??? ??? React ??? ???? ? ??? ?? ? ?? ?? ?????.

1. ???? ?? ?? ??? ?? ??? ???? ??? ??? ?? ??? ?? ?? ? ????. ???? ??? ? ??? ?? ??? ?? "?? ??" ?? ??? ????.

src/
├── components/
│   └── Button/
│       ├── Button.js
│       ├── Button.css
│       └── index.js
├── pages/
│   └── Home.js
└── App.js

????? ??(?? ??)?? ???? ?????? ?? ????? ???? ?? ????? ? ?????.

1. ??? ?? ?? ? ?? ?? React Hooks? ?? ?? ??? ?? ??? ????? ??? ???? ??? ??? ???????. ??? ?? ??? ????? ? ??, ?? ??, ????? ????.

?:

// Instead of class component:
class MyComponent extends React.Component {
  state = { count: 0 };

  increment = () => {
    this.setState({ count: this.state.count + 1 });
  };

  render() {
    return <button onClick={this.increment}>{this.state.count}</button>;
  }
}

// Use functional component with hooks:
import React, { useState } from 'react';

function MyComponent() {
  const [count, setCount] = useState(0);

  return <button onClick={() => setCount(count + 1)}>{count}</button>;
}

1. ???? ??
   ?? ????? ?? ?? ? ???? ?????. ?? ?? ??? ???? ?? ??? ?? ??? ??? ?? ??? ???. ?? ??? ?? ??? ???? ?? ? ?? ?? ?? ??? ??? ?? ????.

2. PropType ?? TypeScript ??
   React? PropTypes ?? TypeScript? ?? ???? ?? ??? ??? ???? ? ??? ? ? ????. ???? ?? ??? ???? ?? ??? ? ?? ??? ? ?? ??? ??? ???? ?????.

PropType? ?:

import PropTypes from 'prop-types';

function Greeting({ name }) {
  return <h1>Hello, {name}</h1>;
}

Greeting.propTypes = {
  name: PropTypes.string.isRequired,
};

TypeScript? ?:

type GreetingProps = {
  name: string;
};

const Greeting: React.FC<GreetingProps> = ({ name }) => {
  return <h1>Hello, {name}</h1>;
};

1. ???? ??? UI? ??? ?? ??? ???? ??? ???? ????? ??? ??????? ?????. ?? ?? ??? ?? ??? ???? ??? ???? ??? ??? ?? ???? UI? ???? ?? ??? ???? ?????.

?? ??? ?:

import { useState, useEffect } from 'react';

function useFetchData(url) {
  const [data, setData] = useState(null);

  useEffect(() => {
    fetch(url)
      .then(response => response.json())
      .then(data => setData(data));
  }, [url]);

  return data;
}

// UI Component:
function DataDisplay({ url }) {
  const data = useFetchData(url);
  return <div>{data ? data.title : 'Loading...'}</div>;
}

1. ?? ?? ??? ?? ?? ??? ?? ??? ???? ??? ? ?? ?? ? ????. ??? ???? camelCase?, ?? ?? ???? PascalCase?, ?? props? ?? ???? ?? ??? ?????.

?:

// Good:
const isLoggedIn = true;
const userProfile = { name: "John", age: 30 };

// Poor:
const x = true;
const obj = { name: "John", age: 30 };

1. Context API? ???? ?????. React? Context API? ????? ??? ???? ??? ????? ?? ???? ???? ??? ????? ???? ???? ? ????. ??? ???? ??? ???????? Redux ?? Zustand? ?? ?? ?? ????? ??? ?????.

?:

import React, { createContext, useContext, useState } from 'react';

const AuthContext = createContext();

export function AuthProvider({ children }) {
  const [isAuthenticated, setIsAuthenticated] = useState(false);

  return (
    <AuthContext.Provider value={{ isAuthenticated, setIsAuthenticated }}>
      {children}
    </AuthContext.Provider>
  );
}

export function useAuth() {
  return useContext(AuthContext);
}

1. ??? ??? ?? ??? ????? React? ?? ?? ??? ?? ???? ??? ?? ??? ?? ??????. ???? ????? ????? ?????? React.memo?, ???? useMemo/useCallback? ?????.

?:

src/
├── components/
│   └── Button/
│       ├── Button.js
│       ├── Button.css
│       └── index.js
├── pages/
│   └── Home.js
└── App.js

1. CSS ?? ?? ??? ?? ?? ?? CSS ??, ??? ?? ?? ?? ??? ??? ???? ?? ???? ?????. ???? ?? ????? ?? ???? ??? ??? ??? ???? ??? ? ??? ???.

CSS ??? ?:

// Instead of class component:
class MyComponent extends React.Component {
  state = { count: 0 };

  increment = () => {
    this.setState({ count: this.state.count + 1 });
  };

  render() {
    return <button onClick={this.increment}>{this.state.count}</button>;
  }
}

// Use functional component with hooks:
import React, { useState } from 'react';

function MyComponent() {
  const [count, setCount] = useState(0);

  return <button onClick={() => setCount(count + 1)}>{count}</button>;
}

??? ?? ??? ?:

import PropTypes from 'prop-types';

function Greeting({ name }) {
  return <h1>Hello, {name}</h1>;
}

Greeting.propTypes = {
  name: PropTypes.string.isRequired,
};

1. ???? ??? ???? ?? ?? ??? ???? ????? ???? ??? ??? ???? ? ??? ???. Jest ? React ??? ?????? ???? ?? ??? ?? ?? ???? ???? ???? ?? ??? ?????.

React ??? ?????? ??? ?? ?:

type GreetingProps = {
  name: string;
};

const Greeting: React.FC<GreetingProps> = ({ name }) => {
  return <h1>Hello, {name}</h1>;
};

??

??? ?? ??? ??? ???? ?? ???? ?? ??? ?? React ??? ??? ? ????. ?? ??, ??? ?? ?? ??, UI?? ?? ?? ? ?? ?? ???? React ??????? ?? ????? ??? ??? ? ?? ? ?? ??? ?????. ????? ??? ??? ???? ?? ??? ??? ?? ??? ? ??? ??? ????.

? ??? ReactJS ?? ??: ???? ?? ?? ??? ?? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!