Calling a VB6 method from a .NET DLL - dll

I have a DLL written in VB 6 and another DLL written in Visual Studio 2005 (VB.NET).
Now I want to invoke the method of the VB DLL from my .NET DLL. What should I do for this?
Any thoughts?

As VB6 creates COM DLLs, Visual Studio should have no problems generating an interop stub for you. Simply add a reference to the VB6 DLL from your .NET project by selecting Add Reference in Visual Studio and finding your DLL under the COM tab. Make sure the VB6 DLL is registered on your machine before you do this.

Related

Using an ActiveX DLL in Visual Studio 2022 causes System.Runtime.InteropServices.COMException

I am trying to build a VB.NET Windows Forms application in VS 2022 using an ActiveX DLL named CP4DLL that I built many years ago in VB6.
I have included a reference to the DLL in the project and the code recognises the objects, methods and properties from the DLL but when I run the VB.NET code it generates the following message:
"System.Runtime.InteropServices.COMException: 'Creating an instance of
the COM component with CLSID {59CA4977-912A-47C6-BAB7-D1B26C0D6ACC}
from the IClassFactory failed due to the following error: 800a0beb
0x800A0BEB.'"
I have a VB6 .EXE application which uses that DLL and when I install it on my computer it and it runs fine.
What else do I need to add to the VB.NET project to solve this problem ?

DLL Project using C++ Not Running in Visual Studio

Working with DLLs using C++, I've come across an issue, the code builds but does not compile/run in Visual Studio. When I use Visual Studio 2017, the problem is "xxx.dll is not a valid win32 application", when using Visual Studio 2010, it's something like "xxx.dll is missing ", the code builds fine, it just doesn't run in Visual Studio, I'm a newbie in DLLs and need to use some sort of debugger.
DLLs don't run. They contain code that is loaded by something else. You can't just run a DLL in Visual Studio. You need an executable (EXE) which loads the DLL.
You can set an executable which runs when you press Start Debugging. This is done in the properties of the project. By default, this is set to the variable $(TargetPath), but you can change this to launch anything under the debugger.
I don't have VS2017, but here is the project properties for VS2015:

Embed Interop Type” property in VS 2008

does “Embed Interop Type” property exist in VS 2008 , and if not What is the alternative ?
Thanks,
Does “Embed Interop Type” property exist in VS 2008?
No. That's part of the C# 4.0 compiler which ships with Visual Studio 2010.
If not What is the alternative ?
You can:
Upgrade to Visual Studio 2010.
Use the C# 4 compiler from the command line and the /link switch.
Not use this feature and have interop assemblies.

How to Call A .NET Created DLL in VB6 Application?

I need to call a VB.NET DLL in VB6 application, does anybody have any ideas?
How to call a Visual Basic .NET or Visual Basic 2005 assembly from Visual Basic 6.0
Using .NET DLL in VB6
You can also export functions as standard windows DLL function entry points if you're willing to use a post compile tool
Check out
http://www.codeproject.com/KB/dotnet/DllExport.aspx
Works a treat and lets you integrate with all sorts of apps using Native VB.net when it'd require C or asm otherwise.

Write VB6 on Visual Studio 2008 without .NET support?

I have to continue to support VB6 applications. I've got both VB6 (Visual Studio 6) installed and Visual Studio 2008 as well. Can I read and write to VB6 projects while in Visual Studio 2008? Will it damage or destroy my VB6 application? It would be very cool if I could free up a lot of space and get rid of Visual Studio 6.
Visual Studio 2008 can't compile VB6 applications. You could use it as a text editor only (though it will offer you the VB.NET IntelliSense, not VB6). However, you need Visual Studio 6 to be able to build your application.
The VB6 IDE will coexist along side the Visual Studio 2008 quite happily.
The VB.NET LANGUAGE is related but not compatible with VB6. Conversion between VB6 and VB.NET is problematic. There are a lot of subtle and gross differences between the two making them effectively separate languages.
You need to keep both separate IDES and libraries installed on your computer in order to deal with both languages.
If you need for the two interoperate you can do this by creating COM libraries. Both languages can consume COM Libraries created in the other.
If you remove VB6 you won't be able to build your VB6 apps? VS2002/3/5/8 doesn't know how to compile VB6 projects.