convert uppercase in javascript code example

Example 1: uppercase javascript

var str = "Hello World!";
var res = str.toUpperCase();  //HELLO WORLD!

Example 2: to capital case javascript

const toCapitalCase = (string) => {
    return string.charAt(0).toUpperCase() + string.slice(1);
};

Example 3: uppercase javascript

var str = "Hello World!";
var res = str.toUpperCase();