Question

The software I am working on was originally written in Delphi, and any recent additions to the software have been done in C#. I would like to derive some C# forms from base Delphi forms. I have managed to get most of it working, except when I try to open the Design view of the C# form in Visual Studio 2008 I get an error. The error message is as follows “Constructor on type’base class’ not found.”

I have done some searching and apparently this is due to the Delphi form not having a default constructor which takes zero arguments. The Delphi TForm class does not have a default constructor which takes zero arguments so I can’t just add one to my Delphi form.

The code I have compiles and runs exactly how I need it to, however I will need to be able to add new components to the C# form in the future. Anyone got any ideas on how I can get the Visual Studio design view working?

Here’s a very simplified version of what I have:

Delphi Code:

type
  TMyDelphiForm = class(TForm)

  private
    ...
  public
    constructor Create(Sender : TObject);
  end;

implementation

  Constructor TMyDelphiForm.Create(Sender : TObject);
  begin
    inherited;
  end;

C# Code:

public partial class MyCSharpForm : TMyDelhpiForm
{
  public MyCSharpForm(Component sender) : base(sender);
  {
    InitializeComponent();
  }
}

Thanks in advance

Answer 1

You cannot mix and match Win Forms and VCL Forms in the same application – period. They are two separate Windows frameworks and are not compatible. The only way to go is to redo the GUI in Visual Studio and link to your non-GUI components built as assemblies through the Delphi.NET compiler.