React useMemo misuse and optimization tips

Today I revisited an important concept in React.js — the Component Lifecycle. Understanding the lifecycle of a component is essential for writing efficient and maintainable React applications. Every React component goes through a series of phases during its lifetime. Key Lifecycle Phases: • Mounting – When the component is created and inserted into the DOM. • Updating – When the component re-renders due to changes in state or props. • Unmounting – When the component is removed from the DOM. In traditional Class Components, lifecycle methods such as componentDidMount, componentDidUpdate, and componentWillUnmount were used to manage these phases. With Functional Components and React Hooks, particularly useEffect(), managing lifecycle-related logic has become simpler and more readable. Mastering the React lifecycle helps developers: ✔ Handle side effects like API calls ✔ Optimize component performance ✔ Write cleaner and more predictable code Learning React is not only about building components, but also about understanding how they behave throughout their lifecycle. #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #ReactLifecycle #ReactHooks #SoftwareEngineering #LearningInPublic

What Runs First in React? Most React developers know what useEffect, useMemo, and useCallback do individually. Far fewer know the exact order they execute in. And that gap causes bugs that are surprisingly difficult to trace. Here is the definitive execution order on first mount: -> Step 1: Rendering JSX React runs the function body of your component first. JSX is evaluated. console.log inside the return runs here. This is the render phase. -> Step 2: useMemo runs during render useMemo executes synchronously during the render phase, not after it. If you have an expensive computation wrapped in useMemo, it runs as part of building the component output. This is why useMemo can be used to compute values that are needed in the JSX itself. -> Step 3: useEffect runs after render After the component has rendered and the DOM has been updated, useEffect fires. It is intentionally deferred. This is where API calls, subscriptions, and side effects belong because they should not block the render. -> useCallback is different from all of them useCallback does not run during mounting. It stores a function reference. That function only executes when it is explicitly called. In the example on the right, increment only logs when you actually call increment(). The final order: Rendering JSX, then useMemo, then useEffect. Why this matters in practice: If you expect useEffect to run before useMemo, your state update will not be available when useMemo computes. If you expect useCallback to run automatically, your side effect will never fire. Getting the order wrong means working with stale data and writing code that behaves differently than you intended. Understanding execution order is not academic. It is the difference between components that behave predictably and ones that produce subtle timing bugs you spend hours debugging. Did you know the exact execution order before seeing this or did it surprise you? #React #ReactHooks #FrontendDevelopment #JavaScript #WebDevelopment #Developers

🚀 React Hooks Small Projects I recently worked on a few small projects to better understand some important React Hooks. In this video, I demonstrated how these hooks work with simple examples so that beginners can easily understand their usage. 🔹 useState – Used to manage state inside a functional component. It helps update and display dynamic data in the UI. 🔹 useEffect – Used to handle side effects in React applications such as API calls, timers, and updating the DOM when state changes. 🔹 useContext – Helps share data globally across components without passing props manually through every level. 🔹 useReducer – A powerful hook for managing complex state logic, especially when multiple state updates depend on different actions. 🔹 useMemo – Optimizes performance by memoizing expensive calculations so they only run when dependencies change. 🔹 useCallback – Returns a memoized function to prevent unnecessary re-renders when passing functions to child components. These mini projects helped me strengthen my understanding of React Hooks and component optimization techniques. 📌 If you watch the video, you can easily understand how each hook works in a practical way. #ReactJS #ReactHooks #WebDevelopment #MERNStack #JavaScript #FrontendDevelopment #CodingPractice

🚀 New Project Update: Quiz Web Application I recently built a Quiz Web Application using React.js and TypeScript, and it was a great learning experience while strengthening my frontend development skills. 🔧 Tech Stack & Concepts Used: • React.js with TypeScript • Trivia API for dynamically generated quiz questions • Styled Components for component-based styling • TypeScript concepts like Enums, Types, and Interfaces • React.FC patterns • Rendering HTML content safely using dangerouslySetInnerHTML (__html) Through this project, I gained deeper hands-on experience with type safety in TypeScript, component structuring, API integration, and modern styling approaches in React. 🎥 I’ve also recorded a demo video showing how the application works. 💻 The source code is available on my GitHub, and I’ll be sharing the repository link https://lnkd.in/gjYYnnnR. 🌐 Next step: Deploying the application on Netlify so everyone can try it online. I’d love your feedback and suggestions! 🙌 #ReactJS #TypeScript #WebDevelopment #FrontendDevelopment #JavaScript #Coding #DeveloperJourney

🚀 useState vs useReducer — When to use what in React? If you’ve worked with React, you’ve probably used useState a lot. But at some point, things start getting messy… and that’s where useReducer steps in. Let’s break it down 👇 🔹 useState Best for simple state Easy to read and quick to implement Great for inputs, toggles, counters Example: const [count, setCount] = useState(0); 👉 Use it when your state logic is straightforward. 🔹 useReducer Best for complex state logic Handles multiple related state updates Keeps logic predictable and organized Example: const [state, dispatch] = useReducer(reducer, initialState); 👉 Use it when: State depends on previous state You have multiple sub-values Logic gets complicated 💡 Think of it this way: useState = Simple & quick 🟢 useReducer = Structured & scalable 🔵 ✨ Pro Tip: If you find yourself writing too many setState calls or nested updates… it’s probably time to switch to useReducer. #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #CodingTips #ReactHooks

𝗠𝗼𝘀𝘁 𝗱𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿𝘀 𝗹𝗲𝗮𝗿𝗻 𝗳𝗼𝗿𝗺 𝗵𝗮𝗻𝗱𝗹𝗶𝗻𝗴. 𝗩𝗲𝗿𝘆 𝗳𝗲𝘄 𝗹𝗲𝗮𝗿𝗻 𝘄𝗵𝘆 𝘁𝗵𝗲𝗶𝗿 𝗮𝗽𝗽𝗿𝗼𝗮𝗰𝗵 𝗶𝘀 𝘀𝗶𝗹𝗲𝗻𝘁𝗹𝘆 𝗶𝗻𝗲𝗳𝗳𝗶𝗰𝗶𝗲𝗻𝘁. Today's class changed how I think about both. Started with the brute force way. One state per input field. Works fine. Also bloats fast and scales terribly. Then the optimized approach. Less code, single state object, same result. But the thing that actually stuck with me was the event system difference nobody talks about early on:  • Native DOM events use event bubbling by default. Events travel up the tree  • React's synthetic events use event delegation by default. One listener at the root handles everything Same outcome on the surface. Very different under the hood. React isn't just a UI library. It's quietly making performance decisions for you before you even think about them. Understanding why React does what it does makes you a better React developer. Simple as that. Devendra Dhote #reactjs #javascript #formhandling #webdevelopment #frontend

🚀 Excited to share my React Complete Guide Presentation! After putting in serious effort, I've created a 21-slide comprehensive ReactJS guide covering everything a developer needs to get started and grow with React! 💻⚛️ 📚 What's covered inside: ✅ Introduction to ReactJS ✅ Environment Setup (Vite + CRA) ✅ JSX — JavaScript XML ✅ Components (Functional & Class) ✅ State Management with Hooks ✅ Props & Data Flow ✅ Validating Props with PropTypes ✅ Component API ✅ Component Lifecycle (Mount → Update → Unmount) ✅ Forms & Form Validation ✅ Event Handling & Synthetic Events ✅ React Best Practices 💡 Whether you're a beginner just starting out or a developer looking for a quick refresher — this guide is for YOU. React is not just a library — it's a mindset of building clean, reusable, and scalable UI components. Once you understand the fundamentals deeply, everything else clicks! 🔥 🎯 Key Takeaways from building this: 👉 JSX makes UI code more readable and intuitive 👉 Component-based architecture = reusability at its best 👉 Understanding the lifecycle is the key to writing bug-free apps 👉 Forms + Events = the heart of every interactive web app 📌 Save this post if you're learning React or planning to start soon! 🔁 Repost to help fellow developers in your network! 💬 Drop a comment — What's YOUR favorite React concept? #ReactJS #React #JavaScript #WebDevelopment #Frontend #FrontendDevelopment #ReactDeveloper #JSX #LearnToCode #Programming #TechCommunity #OpenSource #LinkedInLearning #DeveloperCommunity #100DaysOfCode #CodeNewbie #WebDev #UIComponents #SoftwareEngineering #TechEducation

𝐮𝐬𝐞𝐒𝐭𝐚𝐭𝐞 𝐯𝐬 𝐮𝐬𝐞𝐑𝐞𝐝𝐮𝐜𝐞𝐫 - 𝐖𝐡𝐞𝐧 𝐬𝐡𝐨𝐮𝐥𝐝 𝐲𝐨𝐮 𝐮𝐬𝐞 𝐰𝐡𝐚𝐭? In React, both useState and useReducer are hooks used to manage state inside functional components. However, they are designed for slightly different situations. 𝐮𝐬𝐞𝐒𝐭𝐚𝐭𝐞: useState is ideal for managing simple, independent pieces of state. It works best when the state update logic is straightforward and doesn’t involve multiple conditions or dependencies. Because of its simplicity, it keeps components easy to read and quick to implement. 𝐮𝐬𝐞𝐑𝐞𝐝𝐮𝐜𝐞𝐫: Instead of directly updating state like useState, you define different actions that describe what should happen. A reducer function then decides how the state should change based on that action. This approach is useful when: • Multiple state values are related to each other • State updates depend on different conditions 𝐖𝐡𝐞𝐧 𝐭𝐨 𝐮𝐬𝐞: • useState is great for simple state • useReducer is better for complex state with multiple actions #React #ReactJS #JavaScript #Frontend #SoftwareEngineering #SoftwareDeveloper #Backend #Node

🚀 Starting a 10-part series on React things that make code harder than it needs to be. Not tutorials. Not “10 hooks you should know.” Just real patterns that show up in actual codebases and make simple work more annoying than it should be. Part 1: A lot of React problems are really state problems. Not React itself. Not JSX. Not even hooks most of the time. State living in too many places. Duplicated state. State doing jobs it was never supposed to do. That’s usually when an app starts feeling harder to reason about than it should. The more I work with React, the more I think good frontend code starts with good state decisions. If the state is messy, everything downstream gets harder: debugging feature work testing handoffs even basic collaboration Good React usually feels predictable. And predictable usually starts with state. What’s the most common state mistake you keep seeing? #React #ReactJS #StateManagement #FrontendEngineering #JavaScript #TypeScript #SoftwareEngineering

One React Hook changed the way I build dynamic forms. And honestly, it saved me from a lot of messy code. Before using useFieldArray in React Hook Form, I used manual state for dynamic fields. At first, it looked manageable. But as the form started growing, the logic became messy very quickly. Adding fields, removing fields, keeping values in sync, and handling validation started taking more effort than expected. The feature was simple, but the code was not. Then I started using useFieldArray. That is when I understood how useful this hook is in real projects. It makes dynamic form handling much cleaner. Add and remove actions become easier. The structure feels more organized. And the code becomes easier to maintain. For me, the biggest lesson was simple: Sometimes a problem feels difficult not because it is truly hard, but because we are solving it in a harder way. If you work with dynamic forms in React, this hook is worth understanding deeply. What React Hook made your code noticeably cleaner? #ReactJS #JavaScript #FrontendDevelopment #ReactHookForm #SoftwareEngineering #WebDevelopment #NextJS