IDが一意のキーである以下のオブジェクト配列があります。 "
var test = [
{id: 1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id: 2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode:""},
{id: 1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id: 3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: ""}
]
これから、spreadオペレーターを使用して一意のオブジェクトを取得したいので、以下のコードを使用してみました:
const uniKeys = [...(new Set(test.map(({ id }) => id)))];
Idのみを取得できますが、spread演算子を使用して一意のオブジェクトを取得するにはどうすればよいですか。また、新しいES6機能の実装も役立ちます。
map
メソッドを使用してオブジェクトの配列にfind
戻ることができます。これにより、そのIDを持つ最初のオブジェクトが返されます。
var test = [{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},{id:2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode:""},{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},{id:3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: ""}]
var uniq = [...new Set(test.map(({id}) => id))].map(e => test.find(({id}) => id == e));
console.log(uniq)
代わりにfilter
メソッドを使用することもできます。
var test = [{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},{id:2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode:""},{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},{id:3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: ""}]
var uniq = test.filter(function({id}) {
return !this[id] && (this[id] = id)
}, {})
console.log(uniq)
Set
を使用して、不明なid
でフィルタリングできます。
var test = [{ id: 1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: "" }, { id: 2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode: "" }, { id: 1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: "" }, { id: 3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: "" }],
unique = test.filter((s => ({ id }) => !s.has(id) && s.add(id))(new Set));
console.log(unique);
.as-console-wrapper { max-height: 100% !important; top: 0; }
IDでマップを作成し、値を抽出できます。 [...new Map(test.map(item => [item.id, item])).values()]
var test = [{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id:2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode:""},
{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id:3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: ""}]
console.log([
...new Map(test.map(item => [item.id, item])).values()
])
var test = [{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id:2, PlaceRef: "*00022", Component: "BAXI10R", SubLocCode: "KIT", BarCode:""},
{id:1, PlaceRef: "*00011", Component: "BATH", SubLocCode: "BAT", BarCode: ""},
{id:3, PlaceRef: "*00011", Component: "ANR190", SubLocCode: "B1", BarCode: ""}];
var uniqArray = Array.from(new Map(test.map(e=>[e.id, e])).values());
console.log(uniqArray)