String toUpperCase( )

Converts all characters in this string to upper case. If the string is already in all upper case, this method returns this.

'alphabet'.toUpperCase(); // 'ALPHABET'
'ABC'.toUpperCase();      // 'ABC'

This function uses the language independent Unicode mapping and thus only works in some languages.

Source

/**
 * Converts all characters in this string to upper case.
 * If the string is already in all upper case, this method returns [:this:].
 *
 *     'alphabet'.toUpperCase(); // 'ALPHABET'
 *     'ABC'.toUpperCase();      // 'ABC'
 *
 * This function uses the language independent Unicode mapping and thus only
 * works in some languages.
 */
// TODO(floitsch): document better. (See EcmaScript for description).
String toUpperCase();