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JavaScript React Components (2018) Managing State and Data Flow Update State Based on a Player's Index

Eduardo Osorio
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Eduardo Osorio
Full Stack JavaScript Techdegree Graduate 20,847 Points
Posted by Eduardo Osorio
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Eduardo Osorio
Full Stack JavaScript Techdegree Graduate 20,847 Points

I think this would be a less verbose alternative, that doesn't mutate the previous state directly.

handleScoreChange = (index, delta) => {
    this.setState((prevState) => {
      // New 'players' array – a copy of the previous `players` state
      const players = [...prevState.players];
      players[index].score += delta;
      return {
        players,
      };
    });
  };