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JavaScript React Basics (2018) Understanding State Remove Items From State

Why does he passes a id prop to the Player component if there's already a key prop that could be used instead?

Couldn't the Player's key prop be used as an id?

Mark Sebeck
Mark Sebeck
Treehouse Moderator 36,463 Points

Hi Ewerton. This just showed back up in my que today. Is this something you still need help with? I am not familiar with react but will look into if you are still stuck.

1 Answer

The key is a special string attribute help React identify which items have changed, are added, or are removed. Keys should be given to the elements inside the array to give the elements a stable identity. They're not passed down to children as usable values.

If you try to console.log(props.key) for example, you'll see that it's undefined. Meaning {() => props.removePlayer(props.key)} won't work.