When rendering lists in React, you might have seen a warning about "missing key props". But why do keys matter so much?
๐น What are Keys? โ Keys are unique identifiers that help React efficiently update and re-render list items.
๐น Why Are They Important? โ Without keys, React re-renders everything, making updates slower. Keys help React identify what changed, added, or removed.
๐น Best Practices:
Use a unique ID (like id from a database) as a key.
Avoid using array index unless items never change.
๐น Example:
{todos.map(todo => (
<li key={todo.id}>{todo.text}</li>
))}
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