uppercase letters js code example

Example 1: uppercase javascript

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

Example 2: return first letter of string javascript in uppercase

function capitalizeFirstLetter(string) {
  return string.charAt(0).toUpperCase() + string.slice(1);
}

console.log(capitalizeFirstLetter('foo')); // Foo

Example 3: javascript uppercase string

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