THE MAIN JAVASCRIPT ARRAY METHODS YOU NEED TO KNOW!

push()
This will add an element to the end of an array!

const array = ["hey", "hi", "hello"]
array.push("sup")
array now equals = ["hey", "hi", "hello", "sup"]

THREAD!

#100DaysOfCode #CodeNewbie #javascript

pop()
This will remove the last element of the array!
Super useful!

const array = ["hey", "hi", "hello"]
array.pop()
array now equals ["hey", "hi"]

very simple but useful!

unshift()
This will place the element at the FRONT of the array!

const array = ["hey", "hi", "hello"]
array.unshift("sup")
array now equals ["sup","hey", "hi", "hello"]

shift()
This will REMOVE the element in the FRONT of the array!

const array = ["hey", "hi", "hello"]
array.shift()
array now equals ["hi", "hello"]

splice()
This is a special one that can do a lot! VERY useful!
You can insert, delete and replace with this method!

.splice(position, items to remove)
This is an easy way to explain splice! But I will show multiple use cases so you can be a splice PRO!

const array = [ "hey", "hi", "hello"]
array.splice(1,1)
array now equals = ["hey", "hello"]

It removed the [1] element (we start counting at 0) so it took Hi!

const array = [ "hey", "hi", "hello"]
array.splice(2,1)
array now equals = ["hey", "hi"]

Now how about this?

const array = [ "hey", "hi", "hello"]
array.splice(1,0, "sup")

what do you think is happening here? Think about it for a second before continuing!

the 0 means, we are deleting NOTHING. But we are going to now INSERT "sup" into this position!

so the array will NOW equal
array = ["hey", "sup, "hi", "hello"]

Straight I know! Super useful!

Want to replace something? We can use splice again!

const array = ["hey", "hi", "hello"]
array.splice(0,1, "sup")
array = ["sup", "hi", "hello"]

we went to the 0 element, deleted 1 element and inserted "sup"!

Well, what if we want to keep the original array and make a NEW array, but with only some of the content?
slice() is the answer!

const array = ["hey, "hi", "hello"]
array.slice(0,1)
this would return ["hey"]

array.slice(0,2)
would return ["hey, "hi"]

join()
This will return your array AS A STRING and combine the elements! One of my favorite methods!

const array = ["hey, "hi", "hello"]
array.join()
this will return heyhihello
if we do array.join(" ") it will create a space after each element and return
hey hi hello

concat()
This will combine multiple arrays!

const array = ["hey, "hi", "hello"]
const array 2 = ["sup"]

const new = array.concat(array2)
this will give us ["hey", "hi", "hello", "sup"] the second array is added to the end.

How about sorting values?
we can use sort()!

const numbers = [1, 8 ,99 ,3, 5]

function myFunction(){
numbers.sort(function(a, b){return a-b});
}

This sorting will return the numbers in ascending order
sort(function(a, b){return b-a})
would return the in descending!

What if we just want it reversed?
then reverse() it!

const array = ["hey, "hi", "hello"]
array.reverse();
and it will return ["hello", "hi", "hey"]

Want to just return the array back as a string? Well that's easy!
toString() it!
const array = ["hey, "hi", "hello"]
array.reverse();
this returns hey, hi, hello

what if we wanted to filter() our values?
const varietyOfAges = [18, 44, 16, 12, 60];

function checkIfOldEnough(ages) {
return age >= 18;
}
ages.filter(checkIfOldEnough);

This will filter all of the ages above or equal to 18!

Let me know if this thread helped you! Did I explain things in an easy enough way for you to grasp what I am talking about?

Hope this is a good reference and guide for you to use in the future!

Forgot my most used method!!

map()
Mapping, in simple terms, is when we make a copy of an array & do something to it with a function!

const numbers = [1, 2, 3]
const new = http://numbers.map (myFunction)

function myFunction(num) {
return num * 10;
}

new = 10, 20, 30