title: How to implement IDispatch methods?
body: <p>I have played with a third-party library that is accessed with a COM interface.<br>
  For some tests, I have created the main form as:</p>
  
  <pre><code>TForm1 = class (TForm, IThirdParyCOMInterface)
  </code></pre>
  
  <p>TForm1 implements all methods of IThirdParyCOMInterface, and I get the functionality that I need.</p>
  
  <p>The next step is to create a separate class only for dealing with this COM-Interface.<br>
  Doing something like this:</p>
  
  <pre><code>TMyClass = class (TInterfacedObject, IThirdParyCOMInterface)
  </code></pre>
  
  <p>results in compiler errors:</p>
  
  <blockquote>
    <p>E2291 Missing implementation of interface method IDispatch.GetTypeInfoCount<br>
    E2291 Missing implementation of interface method IDispatch.GetTypeInfo<br>
    E2291 Missing implementation of interface method IDispatch.GetIDsOfNames<br>
    E2291 Missing implementation of interface method IDispatch.Invoke</p>
  </blockquote>
  
  <p>( IThirdPartyCOMInterface = interface (IDispatch) )<br>
  It seems that TForm already implements these IDispatch methods, but my new simple class doesn't.</p>
  
  <p>How can I do this for a new class like the above?<br>
  From which class should I inherit my new class, so that these IDispatch methods are already implemented?</p>
  
  <p>EDIT:<br>
  I just found TAutoIntfObject. Is that what I need?<br>
  (COM is a bit confusing to me, and I am just guessing here)</p>