Attaching Event Listeners with addEventListener in JavaScript

🚀 Preventing Default Event Behavior with `preventDefault` (JavaScript) Many DOM events have default behaviors associated with them, such as submitting a form or following a link. You can prevent these default behaviors using the `preventDefault()` method of the event object. This is useful for overriding the default behavior and implementing custom logic. For example, you can prevent a form from submitting and instead validate the input fields using JavaScript. Use `preventDefault()` judiciously, as it can sometimes disrupt the expected user experience. #JavaScript #WebDev #Frontend #JS #professional #career #development

🚀 Array Methods: splice and slice (JavaScript) The `splice()` method modifies an array by removing or replacing existing elements and/or adding new elements in place. It takes the starting index and the number of elements to remove as arguments, and optionally, new elements to insert. The `slice()` method returns a shallow copy of a portion of an array into a new array object selected from start to end (end not included) where start and end represent the index of items in that array. `slice()` does not modify the original array. #JavaScript #WebDev #Frontend #JS #professional #career #development

🚀 Promises (JavaScript) Promises are objects representing the eventual completion (or failure) of an asynchronous operation and its resulting value. A Promise can be in one of three states: pending, fulfilled, or rejected. Promises provide a cleaner and more structured way to handle asynchronous code compared to callbacks. They allow you to chain asynchronous operations using `.then()` for success and `.catch()` for error handling. Promises make asynchronous code more readable and maintainable, reducing callback hell and improving error handling. The `async/await` syntax is built on top of Promises, making asynchronous code even easier to write and understand. #JavaScript #WebDev #Frontend #JS #professional #career #development

🚀 Day 30 — #React_Conditional_Rendering using && Operator Today I learned how to use the short-circuit #AND (&&) #operator for conditional rendering in React 👇 The && operator is perfect when we want to render content only when a condition is true. ✅ Key Learnings 🔹 Renders JSX only when the condition is true 🔹 If condition is false, React renders nothing 🔹 Best for authentication messages, role-based UI, alerts, and badges 💡 The && operator keeps JSX very clean for one-way conditional rendering. 🔥 Another smart way to build dynamic UI in React. #React #ConditionalRendering #FrontendDevelopment #JavaScript #WebDevelopment #10000 Coders

useEffect runs after every render by default. Here's how to control it: ✅ Run once on mount: useEffect(() => { ... }, []) ✅ Run when a value changes: useEffect(() => { ... }, [value]) ✅ Cleanup on unmount: useEffect(() => { return () => cleanup() }, []) One hook. Three behaviors. Know the difference. 🎯 #ReactJS #Frontend #JavaScript #WebDev

useEffect is probably the most powerful - and most misused - hook in React. 🎯 Arun explained it really well, sharing this because I've made  these exact mistakes in real projects: → Forgetting the cleanup function - memory leaks in production 😅 → Wrong dependency array - stale data showing up in dashboards → Fetching data inside useEffect - unnecessary re-renders and   race conditions What changed for me: ✅ Always write cleanup for subscriptions and event listeners ✅ Use React Query for data fetching — avoids most useEffect complexity ✅ Think twice before adding objects/arrays as dependencies 2.5 years of React and useEffect still teaches me something new. What's your most common useEffect mistake? Drop it below 👇 #ReactJS #Frontend #JavaScript #WebDevelopment #FrontendDeveloper

💡JavaScript Tip💡 Register an event handler to be executed only once. To trigger an event only once, you can pass the { once: true } as a third argument to the addEventListener method like this: 𝗖𝗵𝗲𝗰𝗸 𝗼𝘂𝘁 𝘁𝗵𝗲 𝗖𝗼𝗱𝗲 𝗣𝗲𝗻 𝗱𝗲𝗺𝗼 𝗹𝗶𝗻𝗸 𝗶𝗻 𝘁𝗵𝗲 𝗰𝗼𝗺𝗺𝗲𝗻𝘁 𝘁𝗼 𝘀𝗲𝗲 𝗶𝘁 𝗶𝗻 𝗮𝗰𝘁𝗶𝗼𝗻. 𝘍𝘰𝘳 𝘮𝘰𝘳𝘦 𝘴𝘶𝘤𝘩 𝘶𝘴𝘦𝘧𝘶𝘭 𝘤𝘰𝘯𝘵𝘦𝘯𝘵, 𝘥𝘰𝘯'𝘵 𝘧𝘰𝘳𝘨𝘦𝘵 𝘵𝘰 𝘧𝘰𝘭𝘭𝘰𝘸 𝘮𝘦. #javascript #reactjs #nextjs #webdevelopment

💡 𝗧𝗶𝗽 𝗼𝗳 𝘁𝗵𝗲 𝗗𝗮𝘆 — 𝗥𝗲𝗮𝗰𝘁 𝗗𝗶𝗱 𝘆𝗼𝘂 𝗸𝗻𝗼𝘄? In React, 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻𝘀 𝗱𝗲𝗳𝗶𝗻𝗲𝗱 𝗶𝗻𝘀𝗶𝗱𝗲 𝗰𝗼𝗺𝗽𝗼𝗻𝗲𝗻𝘁𝘀 𝗮𝗿𝗲 𝗿𝗲𝗰𝗿𝗲𝗮𝘁𝗲𝗱 𝗼𝗻 𝗲𝘃𝗲𝗿𝘆 𝗿𝗲𝗻𝗱𝗲𝗿. This means passing them as props can trigger unnecessary re-renders in child components. 🔧 𝗕𝗲𝘀𝘁 𝗽𝗿𝗮𝗰𝘁𝗶𝗰𝗲: - Use "useCallback" to memoize functions when passing them down - Only do this when necessary (e.g., with "React.memo" or dependency arrays) Not every function needs memoization—but knowing when it matters is key. #React #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #PerformanceOptimization #SoftwareEngineering #CodingTips #FullstackDeveloper

💡 𝗧𝗶𝗽 𝗼𝗳 𝘁𝗵𝗲 𝗗𝗮𝘆 — 𝗥𝗲𝗮𝗰𝘁 𝗡𝗮𝘁𝗶𝘃𝗲 𝗗𝗶𝗱 𝘆𝗼𝘂 𝗸𝗻𝗼𝘄? In React, "useRef" 𝘃𝗮𝗹𝘂𝗲𝘀 𝗽𝗲𝗿𝘀𝗶𝘀𝘁 𝗮𝗰𝗿𝗼𝘀𝘀 𝗿𝗲𝗻𝗱𝗲𝗿𝘀 𝘄𝗶𝘁𝗵𝗼𝘂𝘁 𝗰𝗮𝘂𝘀𝗶𝗻𝗴 𝗿𝗲-𝗿𝗲𝗻𝗱𝗲𝗿𝘀. Unlike state, updating a ref 𝗱𝗼𝗲𝘀 𝗻𝗼𝘁 𝘁𝗿𝗶𝗴𝗴𝗲𝗿 𝗮 𝗿𝗲-𝗿𝗲𝗻𝗱𝗲𝗿, making it perfect for: - Storing mutable values - Accessing DOM elements - Keeping track of previous values 🔧 𝗨𝘀𝗲 𝗶𝘁 𝘄𝗵𝗲𝗻: You need to store something that shouldn’t affect the UI. Not everything needs to live in state. #React #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #SoftwareEngineering #CodingTips #BestPractices #FullstackDeveloper

How to prevent unnecessary re-renders in React ⚛️ After understanding why components re-render, the next step is learning how to control unnecessary ones. ⸻ 🔹 React.memo It helps prevent a component from re-rendering when its props haven’t changed. ⸻ 💡 Why it matters: Unnecessary re-renders can affect performance, especially in larger or complex components. ⸻ 🧠 Simple understanding: Same props → no re-render Changed props → re-render ⸻ ⚠️ Important: React.memo is useful, but should be used only when needed. ⸻ Small optimizations can make a big difference ⚡ #ReactJS #FrontendDevelopment #JavaScript #ReactHooks #Performance #LearningInPublic