目录

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.


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 that 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:

Chrome Edge Firefox Safari Opera
Yes Yes Yes Yes Yes

find() is not supported in Internet Explorer 11 (or earlier).