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Aman Kureshi
Aman Kureshi

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React Keys: The Hidden Hero of Lists! ๐Ÿ”‘

When rendering lists in React, you might have seen a warning about "missing key props". But why do keys matter so much?

๐Ÿ”น What are Keys? โ€“ Keys are unique identifiers that help React efficiently update and re-render list items.

๐Ÿ”น Why Are They Important? โ€“ Without keys, React re-renders everything, making updates slower. Keys help React identify what changed, added, or removed.

๐Ÿ”น Best Practices:

Use a unique ID (like id from a database) as a key.
Avoid using array index unless items never change.

๐Ÿ”น Example:

{todos.map(todo => (
<li key={todo.id}>{todo.text}</li>
))}

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