Forgetting to remove event listeners on unmount
A common memory leak issue in React occurs when event listeners aren’t properly removed when components unmount. Here’s how to handle this correctly: The Problem When you add event listeners….
Tag: React
Not handling right-click (contextmenu) events properly
Properly handling right-click events (contextmenu) in React requires understanding both the event system and browser behavior. Here’s a comprehensive guide to avoid common pitfalls: Basic Right-Click Handling Standard Context Menu….
Accessing event.target.value after an asynchronous call (SyntheticEvent is nullified)
In React, when handling events like onChange or onClick, the SyntheticEvent object is pooled for performance reasons—meaning it gets nullified after the event handler finishes. If you try to access….
Passing a function as a prop but forgetting to bind it in class components
Passing a function as a prop without binding it in class components in React can lead to issues where the this keyword doesn’t refer to the correct context, causing errors….
Forgetting default state values in functional components
Forgetting to set default state values in functional components can lead to unexpected behavior, runtime errors, or undefined values in your React app. This issue often occurs when using the….
Using state updates inside a loop without batching
Using state updates inside a loop without batching in React can lead to performance issues, unexpected UI behavior, and inefficient rendering. React’s setState is asynchronous and batches updates for performance…..
Calling setState() with a function but not using previous state
Calling setState() with a function but not using the previous state in React can lead to inconsistent or incorrect UI updates, especially when the new state depends on the current….
Passing an object in setState() without creating a new reference
Proper Object State Updates in React When updating state objects in React, it’s crucial to create new object references rather than mutating existing ones. Here’s how to handle object state….
Mutating props inside a child component
Mutating props inside a child component in React is a common mistake that can lead to unpredictable behavior, bugs, and issues with React’s unidirectional data flow. Props are meant to….
Setting state inside render() leading to infinite loop
Avoiding Infinite Loops from State Updates in Render A critical React mistake is calling state update functions (like setState or state setters from useState) inside the render() method or function….