Here are a few title options, keeping in mind the question format and content focus: Option 1 (Focused on Usage): * How to Master useEffect in React: A Guide to its Different Use Cases Option 2 (E

Understanding useEffect in React

useEffect is a powerful hook in React that allows for side effects in functional components. It provides a clean way to perform tasks like data fetching, event handling, and cleanup operations.

When to Use Effect Hooks with Different Parameters

1. useEffect with no second paraments:

• Syntax: useEffect(()=>{})
• Runs: On every component render.
• Use Cases: Debugging, executing functions on every render.

2. useEffect with second paraments as []:

• Syntax: useEffect(()=>{},[])
• Runs: Once on component mount.
• Use Cases: Initializing component state, data fetching.

3. useEffect with some arguments passed in the second parameter:

• Syntax: useEffect(()=>{},[arg])
• Runs: On change of arg value.
• Use Cases: Running events on props/state change.

Gotchas and Additional Points

• useEffect callbacks execute after the render phase.
• Use caution with stale data due to closures when accessing component state in useEffect.
• Include all relevant dependencies in the second parameter to prevent unnecessary re-renders.
• useEffect callbacks should have a single responsibility.
• Clone values from useRef into useEffect dependencies to avoid potential errors.

Common Patterns

Running once on mount: Use useEffect(()=>{},[]).

Running only on first render: Use const isMounted = useRef(false); in useEffect to check if it's the initial render.

Additional Resources

• [React useEffect API](https://reactjs.org/docs/hooks-reference.html#useeffect)
• [Using the effect hook](https://reactjs.org/docs/hooks-effect.html)
• [A Complete Guide to useEffect by Dan Abramov](https://overreacted.io/a-complete-guide-to-useeffect/)

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