javascript includes() case insensitive

Question

lets say I have an array of filter strings that I need to loop and check against with other passed in string.

var filterstrings = [\'firststring\',\'secondst         


        

Answer 1

ES6 array method filter() can simply the solution in single line, use includes() method to determines whether an array includes a certain value among its entries.

var filterstrings = ['firststring','secondstring','thridstring'];
var passedinstring = localStorage.getItem("passedinstring");

// convert each string from filterstrings and passedinstring to lowercase
// to avoid case sensitive issue.
filteredStrings = filterstrings.filter((str) => str.toLowerCase().includes(passedinstring.totoLowerCase())