Includes() can also be used with strings, where a case-sensitive search is performed if a string is part of a larger corpus of text or not. Please note that if index is greater than or equal to array.length the search will not be performed and false will be automatically returned by includes().

The second parameter defines a position within the array at which the search should begin for the element provided in parameter one.

The elementToFind parameter is rather straight forward - this is what specifies what element we are looking for. Includes() for arrays takes two parameters where the second one is optional: includes (elementToFind, index ) We'll focus on the first two use-cases as those seem to be more common than the other two. There are four ways that the includes() method can be used in JavaScript today: In JavaScript the method we need to use is called includes but that being said, JavaScript also has a contains method but it is for a slightly different purpose. Also, if you come from a different language, for example Java, you'd also be used to using contains on an ArrayList.

Admittedly when it comes to working with JavaScript and arrays, intiutively a lot of people would choose the contains method to check if the array - well, you guessed right, 'contains' - an element.

Array includes javascript