如何取出或更改類陣列物件的鍵名？

我需要在javascript中計算每個子陣列的平均分數。為此，我的目標是為陣列[i][j]做一個雙回圈。但問題是每個子陣列的鍵名或索引陣列高于 18k，所以我的回圈完全溢位！！

通過“我的回圈完全溢位”。我是說：

 for (let i = 0; i < array.length; i  ) {
  console.log(array[i]) 
 };

 /*
   will log =>> nothing stack overflow, stop your code before you start  
   to smell smoke 
 */

為此，我需要更改密鑰名稱或將其取出，但我不知道如何。有什么提示嗎？？或指導方針？？

謝謝

下面是我輸入的小例子（我有 1 個用戶或多或少有 4000 個輸入）：

當前資料：

不知道怎么表達！！

我不知道如何表示影像中顯示的結構......是這樣的

 const results = 
 {
   "18456": [
            {id: 1767, data: "blabla", score: 50, date:'2022-08-02T12:25:00.000Z'},
            {id: 1766, data: "blabla", score: 70, date: '2022-08-02T12:24:00.000Z'},
            {id: 1765, data: "blabla", score: 68, date: '2022-08-02T12:23:00.000Z'},
            {id: 1764, data: "blabla", score: 13, date: '2022-08-02T12:22:00.000Z'}
          ],
   "19212": [
            {id: 1763, data: "blabla", score: 20, date: '2022-07-15T12:25:00.000Z'},
            {id: 1762, data: "blabla", score: 75, date: '2022-07-15T12:25:00.000Z'},
            {id: 1761, data: "blabla", score: 80, date: '2022-07-15T12:25:00.000Z'},
            {id: 1760, data: "blabla", score: 53, date: '2022-07-15T12:25:00.000Z'}
          ],
   "19219": [
            {id: 1763, data: "blabla", score: 100, date: '2022-07-07T12:25:00.000Z'},
            {id: 1762, data: "blabla", score: 69, date: '2022-07-07T12:25:00.000Z'},
            {id: 1761, data: "blabla", score: 32, date: '2022-07-07T12:25:00.000Z'},
            {id: 1760, data: "blabla", score: 58, date: '2022-07-07T12:25:00.000Z'}
          ]
 }

預期輸出：

 result = [
            {averageScore: 50.24%, date:'2022-08-02T12:25:00.000Z'},
            {averageScore: 57%, date: '2022-07-15T12:25:00.000Z'},
            {averageScore: 64.75%, date: '2022-07-07T12:25:00.000Z'},
          ]

非常感謝！

uj5u.com熱心網友回復：

如果您當前的資料如下所示

const arrayLikeObj =
{
  '18456': [
    { id: 1767, data: "blabla", score: 50, date: '2022-08-02T12:25:00.000Z' },
    { id: 1766, data: "blabla", score: 70, date: '2022-08-02T12:24:00.000Z' },
    { id: 1765, data: "blabla", score: 68, date: '2022-08-02T12:23:00.000Z' },
    { id: 1764, data: "blabla", score: 13, date: '2022-08-02T12:22:00.000Z' }
  ],
  '19212': [
    { id: 1763, data: "blabla", score: 20, date: '2022-07-15T12:25:00.000Z' },
    { id: 1762, data: "blabla", score: 75, date: '2022-07-15T12:25:00.000Z' },
    { id: 1761, data: "blabla", score: 80, date: '2022-07-15T12:25:00.000Z' },
    { id: 1760, data: "blabla", score: 53, date: '2022-07-15T12:25:00.000Z' }
  ],
  '19219': [
    { id: 1763, data: "blabla", score: 100, date: '2022-07-07T12:25:00.000Z' },
    { id: 1762, data: "blabla", score: 69, date: '2022-07-07T12:25:00.000Z' },
    { id: 1761, data: "blabla", score: 32, date: '2022-07-07T12:25:00.000Z' },
    { id: 1760, data: "blabla", score: 58, date: '2022-07-07T12:25:00.000Z' }
  ]
};

您可以使用它來獲得所需的結果。

// Extract only values
const result = Object.values(arrayLikeObj).map(m => {
  return {
    // Iterate over every nested object and get the mean of included scores.
    averageScore: m.reduce((acc, obj) => {
      return acc   obj.score;
    }, 0) / m.length   '%',
    // Get first date of nested object.
    date: m.find(f => f).date
  }
});

測驗部分：

const arrayLikeObj = {
  '18456': [{
      id: 1767,
      data: "blabla",
      score: 50,
      date: '2022-08-02T12:25:00.000Z'
    },
    {
      id: 1766,
      data: "blabla",
      score: 70,
      date: '2022-08-02T12:24:00.000Z'
    },
    {
      id: 1765,
      data: "blabla",
      score: 68,
      date: '2022-08-02T12:23:00.000Z'
    },
    {
      id: 1764,
      data: "blabla",
      score: 13,
      date: '2022-08-02T12:22:00.000Z'
    }
  ],
  '19212': [{
      id: 1763,
      data: "blabla",
      score: 20,
      date: '2022-07-15T12:25:00.000Z'
    },
    {
      id: 1762,
      data: "blabla",
      score: 75,
      date: '2022-07-15T12:25:00.000Z'
    },
    {
      id: 1761,
      data: "blabla",
      score: 80,
      date: '2022-07-15T12:25:00.000Z'
    },
    {
      id: 1760,
      data: "blabla",
      score: 53,
      date: '2022-07-15T12:25:00.000Z'
    }
  ],
  '19219': [{
      id: 1763,
      data: "blabla",
      score: 100,
      date: '2022-07-07T12:25:00.000Z'
    },
    {
      id: 1762,
      data: "blabla",
      score: 69,
      date: '2022-07-07T12:25:00.000Z'
    },
    {
      id: 1761,
      data: "blabla",
      score: 32,
      date: '2022-07-07T12:25:00.000Z'
    },
    {
      id: 1760,
      data: "blabla",
      score: 58,
      date: '2022-07-07T12:25:00.000Z'
    }
  ]
};

// Extract only values
const result = Object.values(arrayLikeObj).map(m => {
  return {
    // Iterate over every nested object and get mean of them.
    averageScore: m.reduce((acc, obj) => {
      return acc   obj.score;
    }, 0) / m.length   '%',
    // Get first date of nested object.
    date: m.find(f => f).date
  }
});

console.log(result)

標籤：javascript数组算法嵌套循环

上一篇：StackOverflowException的N個數字的GRC問題

下一篇：如何創建用于在熊貓列中計數的演算法？