After some more research and trial-and-error, I think I found a solution by using System.Collections.ArrayList. However, this does not work with getting a value by index. To do so, I created a new class ComArrayList that inherits from ArrayList and adds new methods GetByIndex and SetByIndex. COM Interop compatible collection: public class ComArrayList : System.Collections.ArrayList … Read more
I was trying to do similar thing. I concluded that the COM library provided by Microsoft is incomplete. I don’t use it because the doc mentioned that “Note: This topic is pre-release documentation and is subject to change in future releases”. So, I decided to take a look at what IISExpressTray.exe is doing. It seems … Read more
It does the same thing as running Regasm.exe with the /tlb and /codebase options. The /codebase option is probably the one you forgot. Regasm likes assuming you put the DLL in the GAC and generates a warning when you don’t. The GAC is indeed a very good way to avoid DLL Hell, always a COM … Read more
You can inherit from StandardOleMarshalObject or ServicedComponent for that effect: Managed objects that are exposed to COM behave as if they had aggregated the free-threaded marshaler. In other words, they can be called from any COM apartment in a free-threaded manner. The only managed objects that do not exhibit this free-threaded behavior are those objects … Read more
COM Automation supports a default property, the property that has dispid 0. This is used in VB6 code to great effect, generating really compact code. A typical example is: rs!Customer = “foo” Which is syntax sugar for: rs.Fields.Item(“Customer”).Value = “foo” Three default properties being used here without being named in the original statement. The Recordset … Read more
The best explanation I’ve seen is in Chapter 7 of the free Foundations of Programming e-book. Basically, in .NET a memory leak occurs when referenced objects are rooted and thus cannot be garbage collected. This occurs accidentally when you hold on to references beyond the intended scope. You’ll know that you have leaks when you … Read more
I know this is old, but there’s an easier way than the listed. This works when you reference two assemblies that share types with the exact same name and namespace. If you right-click on the Reference to your DLL and select Properties, you will see that here’s a property called “Aliases” The default value is … Read more
I’ll take this as a challenge, and will bet the fastest way to shuffle your data between Excel and C# is to use Excel-DNA – http://excel-dna.net. (Disclaimer: I develop Excel-DNA. But it’s still true…) Because it uses the native .xll interface it skips all the COM integration overhead that you’d have with VSTO or another … Read more
Microsoft Office 365 I was running Microsoft Office 365 with Windows 10 and tried the mentioned solutions to remove the registry key without success. I went to the control panel in an attempt to repair the Office 365 suite. Right Click on Start Menu Click Apps and Features Search Microsoft 365 Click Microsoft 365 Click … Read more
This is the answer I wanted to find in StackOverflow but couldn’t. It turns out to be fairly easy to turn a simple C# dll into a COM dll. To create the C# dll Create a solution with a C# class project. The class should have an interface for the properties/methods and an interface for … Read more