title: Max value and numerical validation in KnockoutJS
body: <p>How do I implement a max value validation and check if the observable's value is numerical, something like:</p>
  
  <pre><code>self.MyInteger = ko.observable().extend({ numeric: 2 })
                                 .extend({ maxValue: { params: 255, message: "MyInteger cannot be greater than 255" } });
  </code></pre>