30-seconds-of-code/snippets/js/s/includes-case-insensitive.md

title, type, language, tags, author, cover, dateModified

title	type	language	tags	author	cover	dateModified
Case-insensitive substring search	snippet	javascript	string	chalarangelo	cup-of-orange	2022-07-28T05:00:00-04:00

Checks if a string contains a substring, case-insensitive.

• Use the RegExp constructor with the 'i' flag to create a regular expression, that matches the given searchString, ignoring the case.
• Use RegExp.prototype.test() to check if the string contains the substring.

const includesCaseInsensitive = (str, searchString) =>
  new RegExp(searchString, 'i').test(str);

includesCaseInsensitive('Blue Whale', 'blue'); // true