JAVASCRIPT

how to check if an element is in an array javascript

const fruits = ["Banana", "Orange", "Apple", "Mango"];
fruits.includes("Mango");

how to check if item is in list js

var myList=["a", "b", "c"];
mylist.includes("d")//returns true or false

array value check javascript

const names = ["code","codepadding"]
const key = "codepadding";
var have = names.includes(key) // return true / false
if(have){
	//	do something
}

not in array js

!array.includes("element")

js test if array

if(Array.isArray(myVarToTest)) {
	// myVatToTest is an array
} else {
	// myVarToTest is not an array
}

How do I check if an array includes a value in JavaScript?

Modern browsers have Array#includes, which does exactly that and is widely supported by everyone except IE:

console.log(['joe', 'jane', 'mary'].includes('jane')); //true

javascript check if in array

var extensions = ["image/jpeg","image/png","image/gif"];          
if(extensions.indexOf("myfiletype") === -1){
	alert("Image must be .png, .jpg or .gif");
} 

array check in javascript

const arr = ["name"]
console.log(Array.isArray(arr)); // true

How to Check if an Item is in an Array in JavaScript Using Array.includes()

const nums = [ 1, 3, 5, 7];
console.log(nums.includes(3));
// true

javascript check if array is in array

var array = [1, 3],
    prizes = [[1, 3], [1, 4]],
    includes = prizes.some(a => array.every((v, i) => v === a[i]));

console.log(includes);

how to check if an element is in array javascript

array.includes('element that need to be checked') //returns true or false 

check items in array javascript

function checkAllEven(arr) {
  return arr.every(function(x){
	 return	x % 2 === 0
	})
}

//using "every" to check every item in array.