Answers for "How can JavaScript change the characters in a string to contain only uppercase letters?"

javascript capitalize words

//capitalize only the first letter of the string. 
function capitalizeFirstLetter(string) {
    return string.charAt(0).toUpperCase() + string.slice(1);
}
//capitalize all words of a string. 
function capitalizeWords(string) {
    return string.replace(/(?:^|\s)\S/g, function(a) { return a.toUpperCase(); });
};

check if letter is uppercase javascript

isUpperCase('A') // true
isUpperCase('a') // false