ES6：在数组中查找包含对象ID的对象，并组合总计[重复]

Question

给定这样一组对象：

[
  {
    playerId: 1,
    playerName: "Cooper",
    assists: 1,
    points: 5,
  },
  {
    playerId: 1,
    playerName: "Cooper",
    assists: 3,
    points: 2,
  },
  {
    playerId: 2,
    playerName: "Tom",
    assists: 1,
    points: 3,
  },
  {
    playerId: 2,
    playerName: "Tom",
    assists: 3,
    points: 1,
  },
  {
    playerId: 3,
    playerName: "Shelby",
    assists: 2,
    points: 7,
  },
  {
    playerId: 3,
    playerName: "Shelby",
    assists: 1,
    points: 2,
  },
]

是否有一种方法可以使用ES6在一组对象中找到匹配的对象关键点（本例中为playerId），然后为这些匹配组合其他对象关键点（辅助和点），以便最终的数组如下所示：

[
  {
    playerId: 1,
    playerName: "Cooper",
    assists: 4,
    points: 7,
  },
  {
    playerId: 2,
    playerName: "Tom",
    assists: 4,
    points: 4,
  },
  {
    playerId: 3,
    playerName: "Shelby",
    assists: 3,
    points: 9,
  },
]

Answer 1

你可以使用数组。原型reduce（）。values（）按预期返回数组。

let arrIn = [{"playerId":1,"playerName":"Cooper","assists":1,"points":5},{"playerId":1,"playerName":"Cooper","assists":3,"points":2},{"playerId":2,"playerName":"Tom","assists":1,"points":3},{"playerId":2,"playerName":"Tom","assists":3,"points":1},{"playerId":3,"playerName":"Shelby","assists":2,"points":7},{"playerId":3,"playerName":"Shelby","assists":1,"points":2}];

let arrOut = Object.values(arrIn.reduce((acc, current) => {
  let base = acc[current.playerId];
  if (!base) {
    // if we have not processed an object with this playerId yet,
    // simply copy the current object
    acc[current.playerId] = current;
  } else {
    // otherwise, increase the properties
    base.assists += current.assists;
    base.points += current.points;
  }

  return acc;
}, {}));
console.log(arrOut);