revision:
The Object.fromEntries() static method transforms a list of key-value pairs into an object.
Object.fromEntries(iterable)
Parameters:
iterable : required. An iterable, such as an Array or Map, containing a list of objects. Each object should have two properties:
0 : a string or symbol representing the property key.
1 : the property value.
const entries = new Map([
['foo', 'bar'],
['baz', 42]
]);
const obj = Object.fromEntries(entries);
console.log(obj);
// Expected output: Object { foo: "bar", baz: 42 }
<div>
<p id="from-1"></p>
</div>
<script>
const map = new Map([
["foo", "bar"],
["baz", 42],
]);
const obj = Object.fromEntries(map);
console.log(obj); // { foo: "bar", baz: 42 }
document.getElementById("from-1").innerHTML = "object : " + JSON.stringify(obj);
</script>
<div>
<p id="from-2"></p>
</div>
<script>
const arr = [
["0", "a"],
["1", "b"],
["2", "c"],
];
const object = Object.fromEntries(arr);
console.log(object); // { 0: "a", 1: "b", 2: "c" }
document.getElementById("from-2").innerHTML = "object : " + JSON.stringify(object);
</script>
<div>
<p id="from-3"></p>
<p id="from-4"></p>
</div>
<script>
const object1 = { a: 1, b: 2, c: 3 };
document.getElementById("from-3").innerHTML = "object 1 : " + JSON.stringify(object1);
const object2 = Object.fromEntries(
Object.entries(object1).map(([key, val]) => [key, val * 2]),
);
console.log(object2);
// { a: 2, b: 4, c: 6 }
document.getElementById("from-4").innerHTML = "object 1 : " + JSON.stringify(object2);
</script>