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JavaScript React Components (2018) Managing State and Data Flow Update the Players State Based on Previous State

Posted by Daniel Dayton
Daniel Dayton
4,694 Points

Is there any issue with using prevState.players.push(newPlayer)?

Seems to be working for me, but not sure if there is an issue doing it this way in React.

1 Answer

Lewis Marshall
Lewis Marshall
22,673 Points
Lewis Marshall
Lewis Marshall
22,673 Points

Since you are not allowed to mutate the state directly, you cannot simply push an item to an array. It doesn't leave the array intact but changes it. Instead there should be a new array created which is used to update the state. That's why Guil uses the spread operator to create a new array.

More info about adding an item to an array in react state - https://www.robinwieruch.de/react-state-array-add-update-remove#react-state-add-item-to-array