String.toTitleCase.js

/**
 * Changes the first character of each word to upper case, and any other characters to lowercase.
 * @return {String} String formatted as a title.
 */

String.prototype.toTitleCase = function() {
  var title = this.replace(/([^\W_]+[^\s-]*) */g, function(txt) {
    return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
  });

  lowers = ['A', 'An', 'The', 'And', 'But', 'Or', 'For', 'Nor', 'As', 'At',
    'By', 'For', 'From', 'In', 'Into', 'Near', 'Of', 'On', 'Onto', 'To', 'With'
  ];

  for (i = 0; i < lowers.length; i++) {
    title = title.replace(new RegExp('\\s' + lowers[i], 'g'),
      function(txt) {
        return txt.toLowerCase();
      });
  }

  uppers = ['Id', 'Tv', 'Ii', 'Iii', 'Iv', 'Vi', 'Vii', 'Viii', 'Ix', 'Ny'];

  for (i = 0; i < uppers.length; i++) {
    title = title.replace(new RegExp('\\b' + uppers[i] + '\\b', 'g'),
      uppers[i].toUpperCase());
  }

  return title;
};