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objects

Static object methods​

Oject.assign​

this is the most useful method because it enables merging one or more objects into an existing object and returns the results as an object.

const user = { id: 1, name: "Manuel" };
const modifiedUser = Object.assign(user, { role: "Admin" });

console.log(user); //{ id: 1, name: 'Manuel', role: 'Admin' }

console.log(modifiedUser); //{ id: 1, name: 'Manuel', role: 'Admin' }

console.log(user === modifiedUser); //true

If we observe the consoles, we will see that this method modified the original object, violating the immutability rule and pure functions.

In react projects, we need to avoid this mutations. To solve this problema we can put the {} as the first parameter of the method

const user = { id: 1, name: "Manuel" };
const modifiedUser = Object.assign({}, user, { role: "Admin" });

console.log(user === modifiedUser); //false

another example of object.assign:

const user = { id: 1, name: "Manuel" };
const modifiedUser = Object.assign(
  {},
  user,
  { role: "Admin" },
  { name: "Not Manuel", job: "Developer" }
);

console.log(modifiedUser);

and... another one:

const a = { a: 1 };
const b = { b: 2 };
const c = { c: 3 };
console.log(Object.assign(a, b, c)); //{ a: 1, b: 2, c: 3 }

Object.entries(Objects)​

The object entries returns the entries as an array

Object.entries({ id: 1, name: "Grazi" }); // [["id", 1], ["name", "Grazi"]]

Object.keys​

The objects Keys returns the key's properties as an array

Object.entries({ id: 1, name: "Grazi" }); // ["id", "name"]

Object.values​

The objects values returns the value's properties as an array

Object.entries({ id: 1, name: "Grazi" }); // [1, "Grazi"]