.include in js code example

Example 1: js string contains

var string = "foo";
var substring = "oo";

console.log(string.indexOf(substring) !== -1);

Example 2: javascript includes

const pets = ['cat', 'dog', 'bat'];

console.log(pets.includes('cat'));
// output: true

Example 3: .includes javascript

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: includes()

const str = 'To be, or not to be, that is the question.' 

console.log(str.includes('To be'))        // true
console.log(str.includes('question'))     // true
console.log(str.includes('nonexistent'))  // false
console.log(str.includes('To be', 1))     // false
console.log(str.includes('TO BE'))        // false
console.log(str.includes(''))             // true