JavaScript Array .includes() Method
The JavaScript array.includes() method checks if an array contains a given value and returns either true or false.
Written on August 26, 2021 and takes about minutes to read.
Description
The includes()
method checks if an element exists in an array and will return a boolean
. As you may have guessed, it returns true
if the array has the value and it returns false
if the array does not contain the value.
const insects = ['grasshopper', 'ant', 'hornet', 'fly']
insects.includes('ant') // true
insects.includes('hornet') // true
insects.includes('beetle') // false
Syntax
array.includes(searchElement)
array.includes(searchElement, fromIndex)
Parameters
searchElement
The value that you're checking for in the array.
fromIndex
(optional)
The index in which to start searching for searchElement
. If no value is provided, this method will search from the beginning of the array.
Return Value
This method will return true
if the tested array includes the given value, otherwise it will return false
.
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