Using C# COM in unmanaged C++ project -> First-chance exception at 0x7697C41F (KernelBase.dll)
.net, c#, com, com-interop, visual-c++
Solution
Exceptions whose exception code is less than 0x80000000 are non-fatal exceptions. They tend to be used to pass information. The shoe fits here, exception code 0x04242420 has been reverse-engineered to CLRDBG_NOTIFICATION_EXCEPTION_CODE, type the number in a google query to see the hits. This answer from a Microsoft employee is probably the most reliable one:
Out of curiosity I did a little digging and found that this is actually an undocumented exception (CLRDBG_NOTIFICATION_EXCEPTION_CODE) that is apparently an addition to the IPC protocol used by the managed debugger in the 4.0 CLR. It should be entirely safe to ignore.
Problem
I'm trying to call methods from a C# COM project in an unmanaged Visual C++ solution, but I keep getting the next error ``` First-chance exception at 0x7697C41F (KernelBase.dll) in Program.exe: 0x04242420 (parameters: 0x31415927, 0x6F310000, 0x00BBDAE8). ``` at the next piece of code ``` SalesForceNew::IMyObjectClassPtr p; p.CreateInstance(__uuidof(SalesForceNew::TestObject)); // error SalesForceNew::MyObject mo = p->getObject(1, "a"); ``` However the value of `mo` is as expected (5, "aa"). I import the tlb-file with this line of code: ``` #import "C:\Users\Bob\Desktop\ComTest\SalesForceNew\bin\x86\Debug\SalesForceNew.tlb" named_guids ``` The C# project is as follows: The interface: ``` using System.Runtime.InteropServices; namespace SalesForceNew { [ComVisible(true)] [Guid("22901ACD-CA30-4D3E-B84B-73B707026AE5")] public interface IMyObjectClass { MyObject getObject(int i, string s); } [ComVisible(true)] [StructLayout(LayoutKind.Sequential)] public struct MyObject { public int Getal; public string Text; } } ``` the class implementing the interface: ``` using System.Runtime.InteropServices; namespace SalesForceNew { [ClassInterface(ClassInterfaceType.None)] [Guid("234A2A35-F270-458D-A67B-C834EB794B27")] [ComVisible(true)] public class TestObject : IMyObjectClass { public MyObject getObject(int i, string s) { return new MyObject() { Getal = i * 5, Text = s + s }; } } } ``` I checked the options `Register for COM interop` and `Make assembly COM-Visible` in the properties of the C# COM project. UPDATE: the error won't come up if we change the frameworkversion of the C# COM project to 2.0, 3.0 or 3.5. It only shows up when the frameworkversion is 4.0 or 4.5.