If all you need to do is get a boolean value indicating if the substring is in another string, then this is what you'll want to use. This method was introduced in ES6 and is typically the preferred method for simple use-cases. Keep this in mind when reading the article as it'll likely help you for similar use-cases. ‘amtrack’.Note: The first two methods shown below also works on arrays, which tells you if an array contains a given value (or the index of it for indexOf()). ‘amtrack’.indexOf(‘a’) // 0 – Javascript string contains character check Read: How to remove a property from a Javascript Object You can also pass an optional second parameter to indicate where to start searching.

This method returns an integer with the position of the substring, and if it does not find the substring, it returns -1. ‘AMTRACK’.includes(‘M’, 1) // true Using the indexOf () methodīefore the release of the official method includes(), another way to check if a string contains a substring was to use the method indexOf(). You can optionally pass a second parameter to indicate where to start looking for the substring: Read: How to delete values from an array in Javascript ‘HI WORLD’.toLowerCase().includes(‘world’) // true – javascript string lowercase

Note that the method includes()is case sensitive, so if you want to search for an independent string if it is uppercase or lowercase, you can do the following: ‘Hi world’.includes(‘world’) // true – javascript includes string method The method includes()is the official way to check if a string is contained within another string. In JavaScript there are several ways to check whether a string contains a word or a substring. Checking if a string contains a word is a common task in any programming language.

Javascript string contains substring