从现有地图初始化地图
Initialize map from existing map
假设我们有一个现有地图:
const m1 = new Map([['color', 'red'], ['owner', 'Flavio'], ['age', 2]])
如果我们想创建一个新地图,是否足够做:
const m2 = new Map(m1);
或者可能是:
const m2 = new Map(Array.from(m1))
MDN 说你可以这样做。
const first = new Map([
[1, "one"],
[2, "two"],
[3, "three"]
]);
const second = new Map([
[1, "uno"],
[2, "dos"],
[3, "tres"]
]);
const merged = new Map([...first, ...second]);
console.log(merged.get(1))
假设我们有一个现有地图:
const m1 = new Map([['color', 'red'], ['owner', 'Flavio'], ['age', 2]])
如果我们想创建一个新地图,是否足够做:
const m2 = new Map(m1);
或者可能是:
const m2 = new Map(Array.from(m1))
MDN 说你可以这样做。
const first = new Map([
[1, "one"],
[2, "two"],
[3, "three"]
]);
const second = new Map([
[1, "uno"],
[2, "dos"],
[3, "tres"]
]);
const merged = new Map([...first, ...second]);
console.log(merged.get(1))