gistfile1.js

$('form').submit(function() {
  // get all the inputs into an array.
  var $inputs = $('#form :input');

  // get an associative array of just the values.
  var values = {};
  $inputs.each(function() {
      values[this.name] = $(this).val();
      if ($(this).val() == "") {
        alert("You haven't filled out all the fields");
        return false;
      }
  });
});