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8,611 Pointsi'm keep getting a message in the console
react.development.js:316 Warning: Each child in an array or iterator should have a unique "key" prop.
Check the render method of App
. See https://fb.me/react-warning-keys for more information.
in Player (created by App)
in App
1 Answer
Cheo R
37,150 PointsThe key prop's just react's way to keep track of elements when iterating over them.
You can use the element's index (from the array it's in), but since items can be added/removed from a list, it's better to use something more unique. The key's are for react's internal use.
const food = ['tacos', 'salsa', 'tamarindo', 'torta'];
<ul>
{
food.map((item, index) => <Food key={item.name} obj={item}>);
}
</ul>
Where you can replace item.name with index.