Passing an object from VB6 to C#

[ymak]

Hello,

I am trying to use C# code from VB6 using COM wrapper.
Is there an example on how to pass an object from VB6 to C#?
For example my C# method is public void PassObject(Item itm) where Item is the C# class.
Trying to pass a similar class from VB6 I get the error "runtime error 438 object doesn't support this property or method"

Thank you

[ymak]

My fault.
The "Call" keyword in front of the Sub name was missing (I have not used VB till now)
However now I get "runtime error 430 class does not support automation or does not support expected interface"

[Zakoss]

You could use something like this in c#:

[Guid("fb5e929a-2f8b-481e-9516-97edf5099df4")]
[ComVisible(true)]
public interface myInterface{
public void addObject(string key, string value);
}

And in your class, you could have this:

private collection
public addObject(string key, string value)
{
collection.Add(key, value);
}

This should allow you to call addObject in vb6 and passing your data. Then .net will add it to a collection, so instead of passing your whole collection from vb6 to .net, you pass them one by one

[ymak]

Thank you Zakoss.
I have already implemented a solution like that.
I am just wondering if it possible to use a class instead of separate parameters.
Following that I was planing to pass an array of objects.

[Frinavale]

I have never used .NET objects within a VB6 code base; however you should be able to write interop code to expose the classes and methods you want to consume if you follow the guidelines for Interoperabilit y.

I would research the topic using the MSDN library

A very general starting point would be:

• Interoperabilit y Overview (C# Programming Guide)
• Qualifying .NET Types for Interoperation

According to the second article you should be able to pass classes if the classes are implemented properly for that process.

[ymak]

Thank you Frinavale
After playing around I have managed to pass an object as parameter to c# method.
I still haven't managed to pass an array of objects.

[Frinavale]

ymak,

I'm sorry but in all of my interop usage I have never been able to pass arrays of classes.

I didn't experience any errors but the data did not translate properly between the two memory heaps and so it ended up getting messed up (from what I remember...it has been a long time).

I was hoping you would have better luck.

If you are successful, post back and let me know what you did.

[ymak]

I'll probably implement a solution like Zakoss suggested.
Passing one by one and storing them in a collection