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Understanding Arrays

Dillon on February 14, 2023

To create an array const = arrayName = []; To add items to an array, you can use the .push myToDoList.push(todoA, todoB); alternatively you c...
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Dillon

You can destructure arrays!!!

It's very similar to object destructuring

for example,

const books = [
"My Anthonia",
"The Picture of Dorian Grey",
"A Scarlet Letter"
];

To destructure this array...

const [first, second, third]] = books

If you wanted to destructure books to show only My Anthonia, and create an array with the other two.

you can use an operator that is like the spread operator.

const [favBook, ...otherFavs] = books;

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Dillon

.indexOf tells us where the item is in the array. If not there, it returns a -1

.includes returns a boolean.

syntax => arrayName.includes(itemYouAreTesting)

using the callback function the full syntax is

arrayName.some(arrayName => arrayName.value === true);

basically same syntax as before, but the .every method checks if EVERY unit meets the criteria