JavaScript Array find()

Example 1

Find the value of the first element with a value over 18:

const ages = [3, 10, 18, 20];

function checkAge(age) {
  return age > 18;
}

function myFunction() {
  document.getElementById("demo").innerHTML = ages.find(checkAge);
}
Try it Yourself »

Description

The find() method returns the value of the first element that passes a test.

The find() method executes a function for each array element.

The find() method returns undefined if no elements are found.

The find() method does not execute the function for empty elements.

The find() method does not change the original array.


Array Find Methods:

MethodFinds
indexOf()The value of the first element with a specified value
lastIndexOf()The index of the last element with a specified value
find()The value of the first element that passes a test
findIndex()The index of the first element that passes a test
findLast()The value of the last element that passes a test
findLastIndex()The index of the last element that passes a test

Syntax

array.find(function(currentValue, index, arr),thisValue)

Parameters

function() Required.
A function to run for each array element.
currentValue Required.
The value of the current element.
index Optional.
The index of the current element.
arr Optional.
The array of the current element.
thisValue Optional. Default undefined.
A value passed to the function as its this value.

Return Value

Type Description
A value The value of the first element that pass the test.
Otherwise it returns undefined.

Example 2

Find the value of the first element with a value above a specific number:

<p><input type="number" id="ageToCheck" value="18"></p>

<button onclick="myFunction()">Try it</button>

<p id="demo"></p>

<script>
const ages = [4, 12, 16, 20];

function checkAge(age) {
  return age > document.getElementById("ageToCheck").value;
}

function myFunction() {
  document.getElementById("demo").innerHTML = ages.find(checkAge);
}
</script>
Try it Yourself »


Browser Support

find() is an ECMAScript6 (ES6) feature.

ES6 (JavaScript 2015) is supported in all modern browsers since June 2017:

Chrome 51 Edge 15 Firefox 54 Safari 10 Opera 38
May 2016 Apr 2017 Jun 2017 Sep 2016 Jun 2016

find() is not supported in Internet Explorer.


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