How to check if an Array includes a value in JavaScript

In this tutorial you will learn 5 ways to check if a JavaScript array includes a value.

1. Array.forEach() method

We can iterate through an array to check if the value is present in the array.

forEach() method takes a callback function, which gets executed once for every element in the array.

const countries = ["India", "England", "USA", "Spain"]

let isFound = false;
countries.forEach((country)=>{
  if (country === 'Spain') {
    isFound = true;
    return;
  }
  isFound = false;
})

console.log(isFound) // true

2. Array.includes() method

includes method returns true if a value is present in an array else it returns false.

const countries = ["India", "England", "USA", "Spain"]

countries.includes("France") 
 // false

countries.includes("England") 
// true

3. Array.indexOf() method

indexOf method returns the first index of the matched element, it returns -1 if the value is not present in the array.

javascript const countries = ["India", "England", "USA", "Spain"]

countries.indexOf("France") // -1

countries.indexOf("England") // 1

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## Check for an Object in an Array

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Let's consider we have an array of objects

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javascript const users = [{id: 1, name: 'suraj'}, {id: 2, name: 'Mark'}]

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## 4. Array.some() method

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If you have **an array of objects** and want to know whether an object is present in the array or not then you can consider using `Array.some()`

`some()` method takes a `callback` function, which gets executed once for every element in the array until it finds an element where the callback returns true. 

`some()` returns `true` if the object is present in the array else it returns `false`

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javascript const objectToFind = {id:2, name: 'Mark'}

const isObjectFound = users.some((user)=> { return user.id = objectToFind.id && user.name = objectToFind.name })

console.log(isObjectFound) // true

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## 5. Array.find() method

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It behaves similar to the `some()` method but instead of returning a boolean value, it returns **the matched value from the array** or it returns `undefined` if the value is not present in the array.

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javascript const objectToFind = {id:2, name: 'Mark'}

const foundObject = users.find((user)=> { return user.id = objectToFind.id && user.name = objectToFind.name })

console.log(isObjectFound) // {id:2, name: 'Mark'}

const notfoundObject = users.find((user)=> { return user.id = 3 && user.name = 'Nick' })

console.log(notfoundObject) // undefined

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**Related Solutions**

- [How to add an element at the beginning of an array in JavaScript](/blog/javascript-array-unshift-method)

- [How to uppercase the First Letter of a String in JavaScript](/blog/uppercase-first-letter-in-javascript)

- [How to get the last element of an Array in JavaScript](/blog/javascript-array-get-last-element)

- [How to convert a Decimal to a Hexadecimal in JavaScript](/blog/decimal-to-hexadecimal-javascript)

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