js if exists in array code example

Example 1: javascript array contains

var colors = ["red", "blue", "green"];
var hasRed = colors.includes("red"); //true
var hasYellow = colors.includes("yellow"); //false

Example 2: javascript method to see if item exists in array

var fruits = ["Apple", "Banana", "Mango", "Orange", "Papaya"];
    
    // Check if a value exists in the fruits array
    if(fruits.indexOf("Mango") !== -1){
        alert("Value exists!")
    } else{
        alert("Value does not exists!")
    }

Example 3: see if array contains array javascript

const found = arr1.some(r=> arr2.indexOf(r) >= 0)

Example 4: Checking whether a value exists in an array javascript

const fruits = ['apple', 'banana', 'mango', 'guava'];

function checkAvailability(arr, val) {
  return arr.some(arrVal => val === arrVal);
}

checkAvailability(fruits, 'kela');   // false
checkAvailability(fruits, 'banana'); // true