Check if an array includes a value in Javascript

In this article, I am going to describe 4 methods

- Using The indexOf() method
- Check if array includes a value in Javascript
- Check for NaN
- Check for Undefined

Using The indexOf() method

Using `indexOf()`, we can determine if an element is present in an array or not. Similar to the `includes()` method the `indexOf()` method also works on arrays and, it takes one argument.

See the code below.

var students = [“john”, “jane”, “jim”];

console.log( students.indexOf(“jane”) > -1 );
// true

Even though the `indexOf()` method supports both old and new browsers, it has few drawbacks.

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