Muhammad Arsalan’s Post

🚀 React 19 Just Changed Form Handling Forever In React 18, submitting a form usually looked like this: ❌ useState for loading ❌ manual onSubmit handlers ❌ extra boilerplate for async actions But React 19 introduces a cleaner way 👇 ✅ useActionState + Form Actions Now you can handle form submissions like: Built-in pending state Less code More declarative UI Better integration with Server Actions ✨ Instead of writing multiple lines for loading logic, React gives you: const [state, action] = useActionState(saveProfile) And your form becomes: <form action={action}> #ReactJS #React19 #JavaScript #FrontendDevelopment #WebDevelopment #Programming #SoftwareEngineering #ReactHooks #DevCommunity

React seems magical — until you understand what's happening under the hood. Before diving into hooks, state, and components, every developer should understand these 6 core concepts: 📄 HTML — what the browser shows 🌳 DOM — how the browser stores it ⚡ JavaScript — how you change it 😰 The Problem — why manual DOM updates don't scale ⚛️ React — describe the UI, let React handle the rest ✏️ JSX — the syntax that makes it all clean Save this cheat sheet. Share it with someone learning React. ♻️ Repost if this helped you. #React #JavaScript #WebDevelopment #Frontend #LearnToCode #Programming

Clean #code isn’t about being fancy. It’s about three simple rules: 1️⃣ Use real words, not letters ❌ p, d, x ✅ price, discountPercentage, totalAmount 2️⃣ Break complex logic into steps ❌ return p * (1 - d / 100); ✅ Calculate discount → Subtract → Return result 3️⃣ Name things what they actually do ❌ total() ✅ calculateDiscountedPrice() 🔴 Stop asking: “Does this work?” 🟢 Start asking: “Will I understand this in 3 months?” If the answer is no → spend 1 more minute making it clear. #CleanCode #JavaScript #Programming #WebDevelopment #SoftwareEngineering #DeveloperTips #CodeQuality #Frontend #React #TypeScript #NextJS

🔁 JavaScript Array.reduce() in simple words reduce() means: go through the array and keep adding to one final result. It can give you: ✅ a total (number) ✅ an object (count/group) ✅ a new array (build something) Example: sum of numbers const nums = [1, 2, 3, 4]; const sum = nums.reduce((total, n) => total + n, 0); console.log(sum); // 10 What’s happening here? • total = the running result • n = current item • 0 = starting value So it works like: 0 → 1 → 3 → 6 → 10 That’s it. One loop, one final answer. 💬 Have you used reduce() in a real project yet? #JavaScript #Frontend #Coding #WebDevelopment

In JavaScript, the switch statement is a clean and organized way to handle multiple scenarios from a single expression — perfect when you’d otherwise end up chaining several if/else statements. - Improves readability when there are many possible cases - Use case for each condition and break to avoid “falling through” to the next case - Include default to guarantee a fallback behavior - Great for menus, status, action types, simple routing, and value mapping 💡 Practical tip: when cases start getting complex, consider using functions or mapping objects to keep the code even more scalable. #JavaScript #JS #Frontend #WebDevelopment #Programming #CleanCode #DevTips #Coding #SoftwareDevelopment #Tech

90% of developers get this wrong. Let’s see if you’re in the 10%. What does this code print? let a = 10; { console.log(a); let a = 20; } Comment ONLY ONE answer: A) 10 B) 20 C) ReferenceError D) undefined No googling. No running it. Just reasoning. Understanding scope and the Temporal Dead Zone is what separates memorization from mastery. JavaScript Mastery w3schools.com #JavaScript #CodingInterview #WebDevelopment #SoftwareEngineering #Frontend

Drawers/tabs resetting your inputs? Most of the time it’s because we unmount them on close. That’s why text fields clear, toggles jump back, and even scroll position resets. React 19.2 adds <Activity />: you can switch a subtree to hidden without losing its state. And while it’s hidden, React cleans up Effects and runs hidden updates at a lower priority — less background work, less UI jank. The image shows the exact change. #React #JavaScript #TypeScript #WebDevelopment #Frontend #SoftwareEngineering #WebPerformance #DeveloperExperience #ReactDevelopment #Programming

How react handles batch processing: I used to think every setState triggers a re-render. React is smarter than that. 👇 When multiple state updates happen in the same event loop tick, React often batches them. So if you do: setA(a + 1); setB(b + 1); setC(c + 1); React doesn’t render 3 times. It groups them into one update and does a single render Why this matters Better performance as fewer renders So, If your next state depends on previous state, prefer the functional form: setA(prev => prev + 1); Because batching can make a stale inside the same cycle. #React #JavaScript #Frontend #WebDevelopment #ReactJS #Performance #SoftwareEngineering #Programming #WebDev

Most developers use Mapped Types. Few realize they can use them to 'filter' keys on the fly. Imagine you have a type with 50 properties. You need a new type that only includes keys matching a specific pattern, like those containing the word 'Id'. Not keys you manually list. Not keys you hardcode. But keys that match a rule. This is where selective remapping in mapped types shines. We know we can use the 'as' keyword to rename keys. But the real 'pro move' is knowing what happens when you remap a key to 'never.' In TypeScript, if a key is remapped to 'never', it is removed from the resulting type entirely. And that's an important point to keep in mind because this is what we can use to do a selective remapping in mapped types. By iterating over every key and applying a conditional check: 1. If the key matches your rule - Keep it. 2. If it doesn’t - Remap to 'never.' This pattern is extremely useful in real-world scenarios where you need only specific prefixed keys or you’re building reusable utility types. When you're building utility types, API response handlers, or form schemas, you often need specific subsets of properties. This pattern lets you extract them programmatically instead of maintaining duplicate type definitions. Once you realize you can conditionally 'filter' keys during transformation, you stop fighting the type system and start making it work for you. #TypeScript #JavaScript #Programming #Coding #WebDevelopment

🚀 Just published: Finding the Largest Number in an Array - 7 JavaScript Approaches Think finding max is simple? Think again! ✅ 7 methods compared (from O(n log n) to O(n)) ✅ Common pitfalls ✅ Production-ready solutions Perfect for developers wanting to level up their algorithmic thinking. Read here: https://lnkd.in/dz2zyBP3 #JavaScript #DSA #WebDevelopment #Programming https://lnkd.in/dz2zyBP3