Elegant way to avoid differentiating between upper - and lowercase characters ? (preferable in JavaScript)

Question

Is there an elegant way to treat both lower- and uppercase characters the same ?

Something where

if (char == a) 

Would return true regardless of char being A or a.

Answer 1

Just convert it to uppercase or lowercase first:

if (char.toUpperCase() == "A") {...}
// Or
if (char.toLowerCase() == "a") {...}