Why Array Comparison in React State Is Tricky? If you’ve ever updated an array in React and your component didn’t re-render, you’re not alone. The reason? React compares state by reference, not by value. So if you modify the same array instead of creating a new one, React thinks nothing changed — even if the data inside it did. Never mutate state directly. Always create a new array or object when updating state. #ReactJS #JavaScript #FrontendDevelopment #WebDevelopment
React State Array Comparison Gotcha
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Today I learned something interesting about React's useState. When we call multiple state updates like: setCount(count + 1) setText("Updated") React doesn’t re-render the component multiple times. Instead, React batches these updates together and performs only one re-render. This improves performance and keeps the UI efficient. Understanding these small things happening behind the scenes really helps in writing better React code. #React #JavaScript #WebDevelopment #LearningInPublic
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Level up your React skills! Understanding useState and useEffect is essential for building dynamic, efficient React applications. - useState → Manage and update component state - useEffect → Handle side effects like fetching data - Dependency Array → Control exactly when effects run Master these concepts to write cleaner code, avoid unnecessary re-renders, and enhance the speed and maintainability of your applications! #ReactJS #JavaScript #WebDevelopment #Frontend #ProgrammingTips #ReactHooks
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Controlled Components in React Today I learned about Controlled Components in React. A controlled component is a form element whose value is controlled by React state instead of the DOM. This means React manages the input values using state and updates them through event handlers. 📌 How It Works The input value is stored in state The input field uses that state as its value When the user types, an onChange event updates the state This way React fully controls the form data. Understanding controlled components helped me see how React manages form inputs efficiently. Continuing to build strong React fundamentals step by step 🚀 #ReactJS #FrontendDevelopment #WebDevelopment #LearningJourney #JavaScript
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Most React developers use this pattern every day: setCount(prev => prev + 1) But very few can clearly explain why it’s necessary. In React, state updates are not immediate. They can be batched and executed later, which means the value you’re using (count) might already be outdated when the update actually runs. The functional update avoids this problem. Instead of relying on a potentially stale value, it receives the latest state at the exact moment React processes the update. So instead of saying: “set the value to this” you’re saying: “update based on whatever the current value is” That’s the key difference. This pattern isn’t just syntax, it’s how you avoid subtle bugs when your next state depends on the previous one. #React #JavaScript #Frontend #WebDevelopment #SoftwareEngineering
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I just deleted 30 lines of code from a React component. no refactor. no library. just one hook in React 19. it's called use() — and it changes how you handle async data and context in your components. most devs haven't heard of it yet. swipe through ↓ broke it down simply what's the most boilerplate you've deleted in a single React upgrade? 👇 #react #react19 #javascript #webdev #frontend
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Day 82 / 365 👨💻 Started understanding React state. 🧠 Problem that useState solves ⚙️ How useState works step by step 🔄 Why re-rendering happens ⏳ Why state updates aren’t immediate 🔁 Updater function vs direct value #365DaysOfCode #React #JavaScript #Frontend
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Avoid Unnecessary Re-renders in React Many React applications become slow not because of bad logic, but because of unnecessary re-renders. To understand this better, I prepared a short PDF explaining: -Memoization in React -useMemo vs useCallback vs React.memo -When optimization is useful -When memoization actually makes performance worse -Best practices for real projects Always remember: Measure first, optimize later. Sharing this guide for developers who want to improve React performance. #ReactJS #FrontendDeveloper #CleanCode #PerformanceOptimization #JavaScript
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💡 𝗧𝗶𝗽 𝗼𝗳 𝘁𝗵𝗲 𝗗𝗮𝘆 — 𝗥𝗲𝗮𝗰𝘁 𝗗𝗶𝗱 𝘆𝗼𝘂 𝗸𝗻𝗼𝘄? In React, 𝗳𝗿𝗮𝗴𝗺𝗲𝗻𝘁𝘀 "(<>...</>)" 𝗹𝗲𝘁 𝘆𝗼𝘂 𝗴𝗿𝗼𝘂𝗽 𝗲𝗹𝗲𝗺𝗲𝗻𝘁𝘀 𝘄𝗶𝘁𝗵𝗼𝘂𝘁 𝗮𝗱𝗱𝗶𝗻𝗴 𝗲𝘅𝘁𝗿𝗮 𝗻𝗼𝗱𝗲𝘀 𝘁𝗼 𝘁𝗵𝗲 𝗗𝗢𝗠. Instead of wrapping elements in unnecessary "<div>" tags, fragments keep your markup 𝗰𝗹𝗲𝗮𝗻𝗲𝗿 𝗮𝗻𝗱 𝗹𝗶𝗴𝗵𝘁𝗲𝗿. 🔧 𝗘𝘅𝗮𝗺𝗽𝗹𝗲 𝘂𝘀𝗲 𝗰𝗮𝘀𝗲𝘀: - Returning multiple elements from a component - Avoiding unnecessary DOM nesting - Keeping layouts easier to style Cleaner DOM = simpler layouts and better performance. #React #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #SoftwareEngineering #CodingTips #CleanCode #FullstackDeveloper
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A common React issue that can silently hurt performance ⚠️ While working on a React application, I came across a case where an API was being called multiple times without any clear reason. At first glance, everything looked fine. The component logic was simple and the API integration was correct. But after debugging, the root cause turned out to be related to useEffect. The effect was running on every render because the dependency array was not properly managed. Once the dependencies were corrected, the API calls were reduced to exactly when they were needed. This kind of issue is easy to miss, but it can lead to: 🔹 Unnecessary API load 🔹 Performance degradation 🔹 Unexpected UI behavior In React, always be intentional with your useEffect dependencies. Small oversights can lead to bigger performance problems. #reactjs #frontenddevelopment #javascript #webdevelopment #performance
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