title: DllImport Unmanaged, Non .NET Dll to .NET Project Representing Char * and Void __StdCall
body: <p>I have a DLL non .net and unmanaged written in Borland C++ that I need to import. It returns void and has the identifier __stdcall on the function. It also requires passing of char *. When I try to add it as a reference to my project in VS 2005, it returns an error of not valid assembly. </p>
  
  <p>How can I do this in C#?</p>
  
  <p>This what I currently have and it does not work:</p>
  
  <pre><code>[DllImport ("Project1.dll", CallingConvention=CallingConvention.StdCall)]
      public static extern IntPtr CustomerForm
          (String caption);
  </code></pre>