прописное JavaScript
var str = "Hello World!";
var res = str.toUpperCase(); //HELLO WORLD!
Batman
var str = "Hello World!";
var res = str.toUpperCase(); //HELLO WORLD!const names = ['Ali', 'Atta', 'Alex', 'John'];
const uppercased = names.map(name => name.toUpperCase());
console.log(uppercased);
// ['ALI', 'ATTA', 'ALEX', 'JOHN']
var string = "A string";
var upperCase = string.toUpperCase();
console.log(upperCase); // -> A STRING
var lowerCase = string.toLowerCase();
console.log(lowerCase); // -> a string.toUpperCase()
// Like this:
alert("In upper case: " + "my string".toUpperCase()); // In upper case: MY STRING