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JavaScript React Components (2018) Managing State and Data Flow Adding Items to State

For some reason I'm receiving an error that states: 'this.state.players.map' is not a function. Any ideas?

It compiles successfully.

1 Answer

Steven Parker
Steven Parker
228,196 Points

To enable a precise answer, always show your code or provide a link to a repo or snapshot.

But generally, that message would indicate that the item you are calling a method ("map") on did not get set to an object of the type you are expecting it to be. Quite often it will contain null or be undefined.

So in this case, I would check to see what this.state.players contains.