check existence of array code example
Example: check if array does not contain value javascript
var fruits = ["Banana", "Orange", "Apple", "Mango"];
var n = fruits.includes("Mango"); // true
var n = fruits.includes("Django"); // false
var fruits = ["Banana", "Orange", "Apple", "Mango"];
var n = fruits.includes("Mango"); // true
var n = fruits.includes("Django"); // false