array.contains in javascript 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 array contains

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

Example 3: array includes

let storyWords = ['extremely', 'literally', 'actually', 'hi', 'bye', 'okay']
let unnecessaryWords = ['extremely', 'literally', 'actually' ];

let betterWords = storyWords.filter(function(word) {
  return !unnecessaryWords.includes(word);
});
console.log(betterWords) // ['hi' 'bye' 'okay]

Example 4: js array contains

let fruits = ["Banana", "Orange", "Apple", "Mango"];
let do_contain = fruits.includes("Mango"); // contain: true

Example 5: 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");
}

Example 6: JavaScript Array Methods includes()

const list = [1, 2, 3, 4, 5, 5, 23, 21, 1231, 2434, 443546456, 17];
console.log(list.includes(4));
// --> true