在 JS 中更改對象的結構

Question

const a = {
  0: { country: "france", date:"sfzef"},
  1: { country: "italie", date:"ttttt"},
  2: { country: "belgique", date:"zzzee"}
}

let obj = {}
for (const property in a) {
  obj = {...obj, `${a[property].country}: ${a[property]}`}
}

我想擁有 ：

obj = {
  france: { country: "france", date:"sfzef"},
  italie: { country: "italie", date:"ttttt"},
  belgique: { country: "belgique", date:"zzzee"}
}

我已經嘗試了 4 個小時，提前感謝幫助我的人

Answer 1

當您需要執行對象的鍵/值對時，您已經接近了，但是您正在創建一個字符串。 計算鍵可以用鍵周圍的方括號來完成：

 const a = { 0: { country: "france", date:"sfzef"}, 1: { country: "italie", date:"ttttt"}, 2: { country: "belgique", date:"zzzee"} } let obj = {} for (const property in a) { obj = {...obj, [a[property].country]: a[property]} } console.log(obj);

如果你想避免每次都復制對象，你可以這樣做：

let obj = {}
for (const property in a) {
  obj[a[property].country] = a[property]
}

Answer 2

替代方法：在Object的條目上使用reducer （參見MDN ）

 const a = { 0: { country: "france", date:"sfzef"}, 1: { country: "italie", date:"ttttt"}, 2: { country: "belgique", date:"zzzee"} }; const b = Object.entries(a) .reduce( (acc, [key, value]) => ({...acc, [value.country]: value}), {} ); console.log(b);