You can use the localeCompare() method.
string_a.localeCompare(string_b);
/* Expected Returns:
0: exact match
-1: string_a < string_b
1: string_a > string_b
*/
Further Reading:
- MDN: String.prototype.localeCompare
- Stack Overflow – Is there a JavaScript strcmp()?
- Tutorials Point: JavaScript String – localeCompare() Method