Determine whether a Value is an Array in JavaScript
In this lesson, you will learn how to check if a JavaScript value is an array with isArray() a static method provided by the Array built-in object. This is an alternative to using the operator typeof, since arrays are technically objects.
Instructor: [0:00] When passing a value, sometimes you want to be absolutely sure that whatever you're passing is actually an array. It might be tempting choose a operator typeof, but as you can see here, it will evaluate to an object. This is technically true since arrays are objects.
[0:21] An alternative is to use the built-in method provided by array, called isArray, a static method. Let's pass in our list number two.
[0:34] I'll create list number two here. Let's console.log this. You can see here it returns true.
[0:44] It will return false if it's not an array. Let's pass in a string here. Let's call it list number three. We can see here it returns false.
[0:59] To recap, we use that built-in static method called isArray provided by array to determine if our value that we're passing in is an array. True, if it's an array. False, if it's not.
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