Javascript / ES6 - Uppercase first letter of each word (2 ways) -- via: https://stackoverflow.com/a/4878800

gistfile1.txt

function toTitleCase(str) {
    return str.replace(/\w\S*/g, function(txt){
        return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
    });
}

// or in ES6:

var text = "foo bar loo zoo moo";
const ucfirst = text => text.toLowerCase()
    .split(' ')
    .map((s) => s.charAt(0).toUpperCase() + s.substring(1))
    .join(' ');

'This is a demo'.replace(/\b[a-zA-Z]/g, (match) => match.toUpperCase());

My two cents.

@Ltoya great code all-though it does not work with some french letters:
jérôme" => JéRôMe

Here's another take with regex that works with accents:

function toTitleCase(str) {
    return str.replace(/(?:^|\s)\S/g, (match) => { return match.toUpperCase(); });
}

Example:

toTitleCase("jérôme gabriel")
Jérôme Gabriel