Advanced React Patterns

React offers many powerful patterns that can help you write cleaner, more maintainable code.

Custom Hooks

Custom hooks are a great way to extract component logic:

typescript

import { useState, useEffect } from 'react'

function useLocalStorage<T>(key: string, initialValue: T) {
  const [storedValue, setStoredValue] = useState<T>(() => {
    try {
      const item = window.localStorage.getItem(key)
      return item ? JSON.parse(item) : initialValue
    } catch (error) {
      return initialValue
    }
  })

  const setValue = (value: T | ((val: T) => T)) => {
    try {
      const valueToStore = value instanceof Function ? value(storedValue) : value
      setStoredValue(valueToStore)
      window.localStorage.setItem(key, JSON.stringify(valueToStore))
    } catch (error) {
      console.log(error)
    }
  }

  return [storedValue, setValue] as const
}

Context Pattern

The Context API is perfect for sharing state across components:

tsx

import { createContext, useContext, ReactNode } from 'react'

interface ThemeContextType {
  theme: 'light' | 'dark'
  toggleTheme: () => void
}

const ThemeContext = createContext<ThemeContextType | undefined>(undefined)

export function ThemeProvider({ children }: { children: ReactNode }) {
  const [theme, setTheme] = useState<'light' | 'dark'>('light')

  const toggleTheme = () => {
    setTheme(prev => prev === 'light' ? 'dark' : 'light')
  }

  return (
    <ThemeContext.Provider value={{ theme, toggleTheme }}>
      {children}
    </ThemeContext.Provider>
  )
}

Key Takeaways

Custom hooks promote reusability
Context helps avoid prop drilling
Always consider performance implications
Keep components focused and single-purpose

These patterns will help you build better React applications!