如何從現有的物件陣列創建嵌套物件的新陣列

請幫助重構js中的物件。

const o = [
  {
    id: 1612,
    Tasks: 'Remuneration sheet mentain.',
    calendar_year: 2021,
    calendar_week_in_year: 45,
    WeekStartDate: '2021-10-31',
    WeekEndDate: '2021-11-06',
    status: 'Done',
  },
  {
    id: 1612,
    Tasks: 'Remuneration sheet mentain.',
    calendar_year: 2021,
    calendar_week_in_year: 46,
    WeekStartDate: '2021-11-28',
    WeekEndDate: '2021-12-04',
    status: 'Done',
  },
  {
    id: 1939,
    Tasks: 'Debtors Reconciliation',
    calendar_year: 2021,
    calendar_week_in_year: 45,
    WeekStartDate: '2021-10-31',
    WeekEndDate: '2021-11-06',
    status: 'Done',
  },
  {
    id: 1939,
    Tasks: 'Debtors Reconciliation',
    calendar_year: 2021,
    calendar_week_in_year: 46,
    WeekStartDate: '2021-11-28',
    WeekEndDate: '2021-12-04',
    status: 'Done',
  },
];

const required = [
  {
    id: 1612,
    Tasks: 'Remuneration sheet mentain.',
    week: [
      { w_no: 45, calendar_year: 2021, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done' },
      { w_no: 46, calendar_year: 2021, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done' },
    ],
  },
  {
    id: 1939,
    Tasks: 'Debtors Reconciliation',
    week: [
      { w_no: 45, calendar_year: 2021, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done' },
      { w_no: 46, calendar_year: 2021, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done' },
    ],
  },
];

uj5u.com熱心網友回復：

這實際上只是一個“分組依據”分組，id并在陣列中累積相關屬性。這里使用reduce()和解構來隔離迭代物件的必要屬性。

const o = [{ id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', },];

const result = Object.values(
  o.reduce((a, { id, Tasks, ...week }) => {
    (a[id] ??= { id, Tasks, week: [] }).week.push(week);

    return a;
  }, {})
);

console.log(result);

上面使用邏輯空賦值 (??=)如果出于兼容性原因需要替換它，您可以使用 OR 短路

(a[id] || (a[id] = { id, Tasks, week: [] })).week.push(week);

顯示代碼片段

const o = [{ id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', },];

const result = Object.values(
  o.reduce((a, { id, Tasks, ...week }) => {
    (a[id] || (a[id] = { id, Tasks, week: [] })).week.push(week);

    return a;
  }, {})
);

console.log(result);

但是可讀性比緊湊性好，所以你也可以把它完整地寫出來

if (a[id] === undefined) {
  a[id] = { id, Tasks, week: [] };
}
    
a[id].week.push(week);

顯示代碼片段

const o = [{ id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1612, Tasks: 'Remuneration sheet mentain.', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 45, WeekStartDate: '2021-10-31', WeekEndDate: '2021-11-06', status: 'Done', }, { id: 1939, Tasks: 'Debtors Reconciliation', calendar_year: 2021, calendar_week_in_year: 46, WeekStartDate: '2021-11-28', WeekEndDate: '2021-12-04', status: 'Done', },];

const result = Object.values(
  o.reduce((a, { id, Tasks, ...week }) => {
    if (a[id] === undefined) {
      a[id] = { id, Tasks, week: [] };
    }
    
    a[id].week.push(week);

    return a;
  }, {})
);

console.log(result);

uj5u.com熱心網友回復：

我認為你想要做的是一個嵌套陣列？

我不完全確定您要實作的目標，因為代碼格式不正確，但是請嘗試谷歌搜索嵌套陣列。

應該是這樣的：

{id:   ,Task:    ,Week:[]}

標籤：javascript 数组 目的

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