for循环内的reduce方法 - JS

Question

我正在尝试使用 for 循环遍历条目数组并使用 reduce 方法，但是在第一个条目之后减少 returns，永远不会到达第二个、第三个等条目来推送结果到数组 v.

有什么想法吗？

export const groupEventData = eventData => {
    console.log(eventData)
    // returns[{
    //     "id": "141",
    //     "name": "00333",
    //     "no_transmission": true,
    //     "low_battery" :true,
    // },
    // {
    //     "id": "307",
    //     "name": "01163",
    //     "no_transmission": true,
    //     "low_data_rate": true,
    // }
    // ]

    // now let's group similar event types
    let v = [];
    let types = ["no_transmission", "low_data_rate", "low_battery"]; 
    for (let x = 0; x <= types.length; x++) {
        let data = eventData.reduce((acc, i) => {
            if (!acc[i[types[x]]] && typeof i[types[x]] !== 'undefined') {
                acc[i[types[x]]] = [i]
            }
            else if (Array.isArray(acc[i[types[x]]])) {
                acc[i[types[x]]].push(i);
            }
            else if (typeof acc[i[types[x]]] === 'object') {
                acc[i[types[x]]] = [acc[i[types[x]]]]
                acc[i[types[x]]].push(i)
            }
            return acc;
        }, {});
        // Doesn't add a property for the type if there are no data
        Object.keys(data).length && v.push({ [types[x]: data });
        return v;
    };

}

Answer 1

您的 for 循环中有 return v。尝试将它撞到紧靠其下方的花括号下方。现在 for 循环只迭代一次然后返回一个值。

下面为我工作：

const eventData = [
  {"id": "141","name": "00333","no_transmission": true,"low_battery": true},
  {"id": "307","name": "01163","no_transmission": true,"low_data_rate": true}
]

const type = 'bc'

const types = ["no_transmission", "low_data_rate", "low_battery"]

const groupEventData = (eventData, type) => {
  let v = [];
  for (let x = 0; x <= types.length; x++) {
    let data = eventData.reduce((acc, i) => {
      if (!acc[i[types[x]]] && typeof i[types[x]] !== 'undefined') {
        acc[i[types[x]]] = [i]
      }
      else if (Array.isArray(acc[i[types[x]]])) {
        acc[i[types[x]]].push(i);
      }
      else if (typeof acc[i[types[x]]] === 'object') {
        acc[i[types[x]]] = [acc[i[types[x]]]]
        acc[i[types[x]]].push(i)
      }
      return acc;
    }, {});
    Object.keys(data).length && v.push({ [`${types[x]}_${type}`]: data });
  };
  return v;
}

console.log('groupEventData', groupEventData(eventData, type))

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