title: MustInherit class, derived class, and its class: how to call und initiate?
body: <p>my programming language is VB.Net.</p>
  <p>let'say I have an abstract class</p>
  <pre><code>Public MustInherit Class FR : Inherits UnmanagedObject
  
  End Class
  </code></pre>
  <p>Thus, I have to write a derived class, also including Protected Overrides Sub DisposeObject()</p>
  <pre><code>Public Class derived_Class : Inherits FR
      Protected Overrides Sub DisposeObject()
  
      End Sub
  End Class
  </code></pre>
  <p>How can I use the methods of FR? Where do I have to initiate the derived_class?
  Do I need a third class, like this?</p>
  <pre><code>Public Class next_class
      Public Sub New()
          MyBase.New()
      End Sub
  End Class
  </code></pre>
  <p>According to a documentation, this</p>
  <pre><code>Protected Sub New()
  
      End Sub
  </code></pre>
  <p>has to go somewhere.</p>
  <p><strong>Description of the problem:</strong> Due to the fact that 'FR' has the MustInherit keyword, I cannot write <em>New</em>. Therefore I wrote the derived class.</p>
  <p>Could someone please help me get the whole package up and running ??? I appreciate your help. You can answer in C#, too. There are enough converters I can use, then.</p>