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Defining a DLL entry point in C#? (DLLEXPORT not DLLIMPORT)

I want to call a DLL class library written in C# from unmanaged C++. I saw this example: http://msdn2.microsoft.com/en-us/library/2x8kf7zx.aspx. It works so I tried to transfer it to my files. I got a System.EntryPointNotFoundException. The problem is: How do you define an entry point in a C# DLL? The C++ seems to work so the error must be in the C# DLL.

lagu26537

hi there,

The error that you are getting means that either the function name is in-correct or the parameters that are provided by you are not proper.

Please check the name of the function and its parameters as well its datatypes.

Secondly initially in the Classic VB 6.0 \ VC++ days there use to be a tool called as API viewer using which you can view the function's name and its parameter. Try to get that tool or you can also visit the http://www.pinvoke.net site to check out the details of the unmanaged API.

Regards,

Nasha {MVP}.

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Nasha

The DLL is not unmanaged. It is managed. I have source code for both projects the .exe and the .dll. I wrote both of them today. It is the .exe-file which is unmanaged (Win32 Console application (C++). It has to be unmanaged because that's the situation in the real project.). The DLL is a C# class library. What C# lines of code do you put in the DLL C# class library in order to create an entry point?

I checked with $ dumpbin.exe -exports CSTaxCalc.dll It returned:
----------------------------------------------------------
$ dumpbin -exports CSTaxCalc.dll
Microsoft (R) COFF/PE Dumper Version 8.00.50727.42
Copyright (C) Microsoft Corporation. All rights reserved.

Dump of file CSTaxCalc.dll

File Type: DLL

Summary

        2000 .reloc
        2000 .rsrc
        2000 .text
----------------------------------------------------------
So there are no entry points in the DLL-file. Don't you have to put in lines of code to get entry points into the DLL? Like e.g.

----------------------------------------------------------
extern "C" __declspec(dllexport) __cdecl
                          int summis(int a,int b);
----------------------------------------------------------

Thanks, Lars

lagu26537

i have this problem too..

And i`m made my dll in c# , and when i tryed to use DLLIMPORT same exception occured.. i know that my dll is a valid COM but what if i want to use the DLLIMPORT ???

#include "Univers.h"

zapacila89

C# doesn't support this.

Mattias, C# MVP

Mattias Sjögren

There's an example in chapter 21 of Sam's teach yourself Visual C++ .NET (2002) that does just this. The problem is that the recepy they describe doesn't work in VS 2005. If you import the solution to VS 2005 you get compiling errors.

lagu2653

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