title: Property grid only show some category
body: <p>I got a PropertyGrid that is use on an object that have the following property category : Style, Calcul and Misc</p>
  
  <p>What I want is to only show to the user the Calcul category, but I don't want to use the browsable attribute because I want all these property to be visible in Visual studio.</p>
  
  <p>So, what I need, is an in-code solution.</p>
  
  <p>I use .Net 3.5 c#</p>