Examples on how to use the forEach, reduce, map and filter methods in JavaScript

Answer 1

I can answer forEach for you!
take a look at this code snip I have for a Discord bot I’m making:
function multiplyCommand(arguments, recievedMessage){
if(arguments.length < 2){
recievedMessage.channel.send('I can\'t multiply that.')
}
let product = 1
arguments.forEach((value) => {
product = product * parseFloat(value)
})
recievedMessage.channel.send('The answer is ' + product.toString())
}
The code is saying that for every value that is inputed, it will multiply it by the other values that are input.
Simply put: forEach will execute any code inside the curly braces for every single thing in the parameters.
Correct me if i’m wrong.

Answer 2

https://code.sololearn.com/WQ73sGfyb36k/?ref=app#js

Answer 3

You can learn from Daniel's 10 Array method
https://code.sololearn.com/WopAH9yrs62D/?ref=app
His other tutorials:
https://code.sololearn.com/WKFF4vOCr3mi/?ref=app

Answer 4

forEach is used to perform a function for each element in an array e.g
Es6 :
var fruits = ["apple", "banana"] ;
fruits.forEach((fruit) =>{
console.log(`The fruit is ${fruit} `) ;
} ) ;
Or..
var fruits = ["apple", "banana"] ;
fruits.forEach(function(fruit)
{
console.log("The fruit is " + fruit) ;
}
) ;
The forEach array method can e used in place of a for loop eg:
Es6:
var fruits = ["apple", "banana"] ;
for(let fruit of fruits)
{
console.log(`The fruit is ${fruit} `) ;
}
, in the forEach, the parameter passed to your function is a variable that represents each element of your array, it can be named anything, it took me a while to understand too, but its nice to use, i also originally came here to search how to use the reduce array method, but ill just share what i know, andvin case u dont understand te es6 for...of loop, here's the equivalent :
for(i = 0;i<fruits. length;i++) {
console.log("The fruit is "+ fruits[i]) ;
}
Hope that helped

Answer 5

https://code.sololearn.com/WVnXtMxOdp4d/?ref=app