Easy way to make a com DLL in c#?

claras2005

Hi

I am currently playing around with visual studio C# express 2005 beta 2 and want to make a dll that I can use as an automation from within Navision. I have done this sometimes before with VB .net and it was relatively easy because there is a wizard to make the comclass . But how do I do this in C#?

DenSter

It shouldn't matter if you use VB.NET or C#, since they are both using the same runtime and tools. It looks to me that you are using a VS beta that probably does it differently. Have you checked the public C# newsgroups on news.microsoft.com?

claras2005

I have searched the net a little but I have no solution.

I found this:

http://www.codeproject.com/csharp/CSCom ... ect=905084

It seems that is not because i am using a Beta, somehow there a differences between the tools you have on VB.net in comparison to C# .net

So I still need help Anyone who have made a dll for navsion using C# pls help! Even with input on how to manually make the DLL

fb

Have you followed the link listed here?:

http://www.mibuso.com/forum/viewtopic.php?t=6955

claras2005

No but it looks really promissing

Thx for the link, I think that will make it work

claras2005

Hmmmm

I have tried his example, I can build the dll and all. But I cannot register it

not with regsvr32 (dllregisterserver is missing error), not with regasm.exe (no valid assembly error) and not from within navision (could not register OLE).

Any ideas what I need to do?

Luc_VanDyck

Maybe this helps: How to register .NET Component for use with Navision ?

claras2005

Eventhough the link had some nice info it did not help me (probably because im stupid).

I still get an error when i use regasm.exe. It tells me that it could not read the file because its not a valid assembly.

Do any of you have a small C# demo project they could share? Just a hello world function that can be called from navsion so that I can check it up against my code? I probably have a small detail wrong.

What I have done so fare:

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

namespace ClassLibrary1
{
    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]

    public interface INavisionTest
    {
        int Add2Numbers(int a, int b);
    }

    [ClassInterface(ClassInterfaceType.None)]

    public class NavisionTest : INavisionTest
    {
        public NavisionTest()
        {
        }

        public int Add2Numbers(int a, int b)
        {
           return (a + b);
        }
    }
}

I have set the properties in the assembly to show com and the interop property in the project is also set to true.

claras2005

Sometimes one gets the best ideas while sleeping J

When I woke up this morning I had the idea that it might be the regasm.exe that I was using that gave me the problem. So I searched my hard disk for the newest version, and you know what I found a newer one! And now I can create the assembly. As I had to go to work I have not tested the DLL yet but I am pretty sure everything will work out fine now!

Funny how one can focus so much on finding an error in the code and then totally overlook the real simple solution J

Thx for all the excellent input to my forum thread and sorry for all my stupid noob questions!

Ill post a entry when I have everything working.

DenSter

There is no such thing as stupid noob questions. You are doing stuff that very few people do, so you're way ahead of many of us. If you're willing, I would be interested to see a little working sample, maybe in the tips and tricks section, or even a download.

claras2005

When (and if) I have something working I will post an example of a small hello world dll or something.

demy75

I've written a post on my blog on how to write a DLL that works with Navision.
Check it here:
http://demiliani.com/blog/archive/2005/09/19/2965.aspx

kine

Easy way:
1) run Visual Studio (I am using 2003 .Net)
2) File - new - project
3) Visual C# - Windows Control Library (or Class Library), enter the name
4) Define what you need to do (all methods you want to public must be defined as public...)
5) use

	[ClassInterface(ClassInterfaceType.AutoDual)]

before your class definition
(using System.Runtime.InteropServices;)
6) Open properties for your project, Configuration properties - Register For COM interop = true
7) Build the project
8) use it in Navision...

MrWho

Hi, thanks for the tip, it worked great!

But is there a way to execute the "Windows Control Library" itself, so it will be shown in Navision. Or is that impossible since there`s nothing to add it on to?

kine

Because I am begginer in C#, I do not know how to "public" something through inheritance (to not need define each function I want to public once more...)

DenSter

I don't know what you mean by 'windows control library', but you can check the automation server list for what is available. One of my coworkers got the speech thing to work, and now he's putting in all sorts of messages in his test databases :roll:

Open the globals or the locals and go to the variables tab. Enter a variable name, set the type to automation and click the look up button. From there on out it's basically a trial and error process.

MrWho

Thank you for the answer, but I find my answer in Navision 4.00 Development II chapter 9, where it says "However, Microsoft Navision only supports non-visual controls".

So, then there`s no point in using Windows Control Library, you can just use Control Library, since "Windows Control Library" can`t be added or shown anyhow in Navision.

ta5

Hi
I tried this in Visual Basic with info from demy75

I've written a post on my blog on how to write a DLL that works with Navision.
Check it here:
http://demiliani.com/blog/archive/2005/09/19/2965.aspx

my vb class:

Imports System.Runtime.InteropServices ' für "<ClassInterFace..."
Imports System.Reflection
Public Interface INavControl
    Function hellofrom_dotNet() As String
End Interface
<ClassInterface(ClassInterfaceType.AutoDual)> _
Public Class FirstNaviClass
    Implements INavControl
    Public Function hellofrom_dotNet() As String Implements INavControl.hellofrom_dotNet
        Return "Hello from dotnet"
    End Function
End Class

So far it works, what puzzles me is that in the symbol menu in Navision I see some Functions and Properties which I did not define myself (Equals, GetHashCode,GetType,ToString).

Thank you in advance
Thomas

kine

Yes, I am solving same thing in Visual Studio 2005 now. What I found yet is, that the DualInterface is not recommanded. But I do not know, how to do it without this... If I do not use this, I do not see the functions and properties in Navision... (and I do not want to use external tools)...

claras2005

It must be possible to make some kind of visual DLL because if you check the mibuso download section someone has made a mini internet browser in navision form via a DLL. And some other guy has made a treeview using delphi.

kauffmann

Here is an C# example of how to code a .Net dll that is available to Navision, without exposing all of the default Com methods.

This example will expose just one property: HelloWorld()

using System;
using System.Runtime.InteropServices;

namespace WhatEver
{
	
  public interface IMyClassInterface
  {
    [DispId(1)]
      string HelloWorld {get;}
  }

  [ClassInterface(ClassInterfaceType.None)]
  [GuidAttribute("E0A33D6F-FCD2-4e85-9A2D-1A908EC39598")]
  public class MyClass : IMyClassInterface
  {
    public MyClass() {}

    public string HelloWorld
    {
      get
      {
        return("Hello World!");
      }
    }
  }
}

kine

Ok, thanks, it seems that the [DispId(x)] is the key I need... :-)

kauffmann

Yes, the fixed DispId is the key factor here.

My thoughts about this: Navision is not capable of using late binding. For that reason you have to know the DispId at designtime. Specifying the DispId in your interface makes the DispId fixed, so Navision is able to store the correct DispId during compilation and use it runtime.

ta5

Hi
I've adapted the c# code (from "kaufmann") to vb.net, looks like this:

Imports System.Runtime.InteropServices
Imports System.Reflection
<InterfaceType(ComInterfaceType.InterfaceIsIDispatch)> _
Public Interface INavControl
    Function hellofrom_dotNet() As String
End Interface
<ClassInterface(ClassInterfaceType.None)> _
Public Class FirstNaviClass
    Implements INavControl
    Public Function hellofrom_dotNet() As String Implements INavControl.hellofrom_dotNet
        Return "Hello from dotnet"
    End Function
End Class

The default com methods are not shown any more in Navision, but still INavControl and FirstNaviClass are both visible. Is there a possibility to avoid that?
Regards
Thomas

kauffmann

By default, the interfaces used by a .NET Class are transformed to dual interfaces in the IDL. This allows the client to get the best of both early binding and late binding. However, there may be occasions when you want the interface to be a pure-dispinterface or a custom IUnknown only based interface. You can override the default type of the interface using the InterfaceTypeAttribute.
To have the Interface hidden for Navision you have to specify that the Interface is type IUnknown.
By using

<InterfaceType(ComInterfaceType.InterfaceIsIUnknown)> _
Interface MyInterface

However, this will hide the interface information of the methods and properties. If you try this you will see that Navision is not able to determine the return type of the methods and instead is using something like

HRESULT = Property(VARIANT parameter)

The other option is to specify your Class as DualInterface. Because every .Net class derives the base interface from the _Object interface, you will see that the Equals, ToString and GetHash methods are specified, along with your interface methods.

ta5

Thank you!
Regards
Thomas

kine

Still have problem with visibility of the functions and properties...
I am using VS 2005.

Example of my code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Reflection;
using System.Runtime.InteropServices;

namespace MyWrapper2005
{
    [GuidAttribute("MyIFGUID")]
    interface IWrapperClass
    {
        [DispId(1)]
        string Property1 { get; set; }
        [DispId(2)]
        public void Function1(string x, string y, short zoom);
    }

    [ClassInterface(ClassInterfaceType.None)]
    [GuidAttribute("myGUID")]
    public partial class WrapperClass : Form, IWrapperClass
    {
        public string Property1        {
            get
            {
                return Component.Property1;
            }
            set
            {
                Component.Property1 = value;
            }
        }
        public void Function1(string x, string y, short zoom)
        {
            Component.Function1(x, y, zoom);
        }
    }
}

But still I am not able to see the properties (I see only the class in Navision, not the interface). I am using StrongName for the class...

I have "Make assembly COM-visible = true" in Project property, "Register for COM interop = true".

Have someone tip where can be the problem?

The class is wrapper for one Automation, which I am opening in new window (it is why the class is inherited from Form class) and on this form I placed visual component "Component".
When I use ClassInterfaceType.AutoDual, I can use the class without problems (but I see all the functions and properties from _Object)...

kauffmann

Try to add the attribute

[InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]

to your interface.

kine

Added, without success... :-/

kauffmann

Obviously you are already using Visual Studio 2005. Maybe there is an difference between registering components for ComInterop between Visual Studio 2003 and 2005:?: I'm not sure, but will test it today or tomorrow.

kine

How can I unregister the .net interop DLL? (I know only the way of regsvr32 but this is not the correct one in this case)