toUpperCase() is not making the string upper case

Question

I don\'t know what I\'m doing wrong; But somehow .toUpperCase() String-function is not working on my browser or do I get something wrong?

var string          


        

Answer 1

toUpperCase returns the new string, so you must write:

string = string.toUpperCase();

In many languages, strings are immutable, meaning that they can not be modified once created. While this costs in efficiency, it is important for object oriented programming, because if a String passed by reference to a function was modifiable, the state of objects could be changed without the object's consent.