C# – Call C# dll from Delphi

.netc++delphimanaged-code

I composed .Net 3.5 dll with single method, which is to be called by Delphi .exe.
Unfortunately it does not work.

The steps:
1. Create C# 3.5 dll with the code:

public class MyDllClass
{
    public static int MyDllMethod(int i)
    {
        MessageBox.Show("The number is " + i.ToString());
    }
}

Go to Assembly Properties –> Assembly Information and checked the "Make Assembly COM-Visible"
Used RegAsm.exe to register my dll

This throws Delphi exception which indicates it cannot connect the dll.
What are the steps required to enabled usage of C# managed dll from unmanaged code.

Does any one familiar with good example about the subject?

Thank you

Best Solution

You may have more luck skipping the COM part by using my project template for unmanaged exports

class MyDllClass
{
    [DllExport]
    static int MyDllMethod(int i)
    {
        MessageBox.Show("The number is " + i.ToString());
        return i + 2;
    }
}

In Delphi, you'd import it like so:

function MyDllMethod(i : Integer) : Integer; stdcall; extern 'YourAssembly.dll';

I had to vote your question down, though. For not even caring as much as to provide code that would compile. (your C# method doesn't return a value, yet it expects as int)

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C# – How to use reflection to call a generic method

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Best Solution

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