javascript object from entries code example

Example 1: javascript object entries

// Object Entries returns object as Array of [key,value] Array
const object1 = {
  a: 'somestring',
  b: 42
}
Object.entries(object1) // Array(2) [["a", "something"], ["b", 42]]
  .forEach(([key, value]) => console.log(`${key}: ${value}`))
// "a: somestring"
// "b: 42"

Example 2: javascript convert Object.entries back to object

const arr = [ ['0', 'a'], ['1', 'b'], ['2', 'c'] ];
const obj = Object.fromEntries(arr);
console.log(obj); // { 0: "a", 1: "b", 2: "c" }

Example 3: js object entries

var obj = { foo: 'bar', baz: 42 };
console.log(Object.entries(obj)); // [ ['foo', 'bar'], ['baz', 42] ]

// objeto array-like
var obj = { 0: 'a', 1: 'b', 2: 'c' };
console.log(Object.entries(obj)); // [ ['0', 'a'], ['1', 'b'], ['2', 'c'] ]

Object.entries(obj).forEach(([key, value]) => {
    console.log(key + ' ' + value); // "a 5", "b 7", "c 9"
});

Example 4: javascript fromEntries

// JS fromEntries => list of key-values transformation into an object
    const keys = ["name", "species", "age", "gender", "color"];
    const values = ["Skitty", "cat", 9, "female", "tabby"];
    const run = document.getElementById("run");
    run.addEventListener("click", function () {
     	let createObj = [];
        keys.forEach((item, index) => {
            createObj.push([item, values[index]]);
        });
        const object = Object.fromEntries(createObj);
        console.log(object);
    });
// expected output = Object { name: "Skitty", species: "cat", age: 9 etc..}