Clr Dll loaded by test prog but not by calling app

问题

I want to develop a plugin for a program (EXE) to interop with an external C# module. The plugin is one of the three dlls needed: this dll (A) calls a wrapper dll (Native/Managed, in C++/Cli) (B) to interop with a C# dll (C).

A is supposed to be loaded by a calling program (EXE) when deployed.

In testing, a message from the C# dll is displayed, which tells me dll A is correctly loaded by a C++ tester and subsequently has made successful call to other dlls.

In deployment, dll A is loaded by EXE if it only displays a message. However, when lines of code to call dll B are added, EXE no longer recognizes dll A.

I have made sure that all files are in the right place. So I think the problem lies in the extra lines of interop code to call dll B. Any idea as to where I should look for problem?

Here is the exported function in dll A:

int WINAPI Init()
{
    FILE * pConsole;
    AllocConsole();
    freopen_s(&pConsole, "CONOUT$", "wb", stdout);
    printf("Started\n");

    //These two line below call the wrapper dll B
    // which serves as a middle man between dlls A and C
    NativeExport_ClientWrapper* client = createMyClass();
    if (client) client->Test();

    return 1;
}

Here is the unmanaged side of the wrapper B:

//----------------------------------------------
//NativeExport_ClientWrapper.h
//----------------------------------------------
//#pragma once

#pragma once
#pragma unmanaged

#define THISDLL_EXPORTS
#ifdef THISDLL_EXPORTS
#define THISDLL_API __declspec(dllexport)
#else
#define THISDLL_API __declspec(dllimport)
#endif


class ILBridge_ClientWrapper;
class NativeExport_ClientWrapper {
private:
    ILBridge_ClientWrapper* __bridge;
public:
    NativeExport_ClientWrapper();
public:
    ~NativeExport_ClientWrapper();
public:
    THISDLL_API void Test();

};
extern "C" THISDLL_API  NativeExport_ClientWrapper* createMyClass();

And here is the managed side of the wrapper:

//----------------------------------------------
//ILBridge_ClientWrapper.h
//----------------------------------------------
#pragma once
#pragma managed
#include <vcclr.h>

class ILBridge_ClientWrapper {
private:
    gcroot<Client^> __Impl;
public:
    ILBridge_ClientWrapper() {
        __Impl = gcnew Client;
    }
    void Test() {
        __Impl->test();

    }

};

回答1:

After exhaustive search, I found nothing that helps to resolve this issue, including doing library load debugging.

My other related posting is here: Unexpected Stackoverflow exception using CLR in a dll

And finally, by doing several things, this exception is gone and everything works now:

1) In my CS project, I use the unmanagedexports package (use NuGet package manager to install it: Install-Package unmanagedexports) to export static methods using the __stdcall calling convention. In this project, you need to add these:

using System.Runtime.InteropServices;
using RGiesecke.DllExport;

2) add the path to the wrapper header files to the unmanaged C/C++ project's property page (C/C++->general->additional include directories)

3) put the managed and native wrapper into one project/dll (built with /clr option), separate them from the other two modules (one for the managed C# and one for the unmanaged C/C++)

4) optionally, I added a definition file for the unmanaged C/C++ functions

5) make sure all modules are built against the same framework and platform. In my case, I use framework 4.0 and x86 platform. In some case, you need to add an app.config file with the following:

<configuration>
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
  </startup>
</configuration>"

6) set the path in the environment pointing to where the dlls are deployed

That's about it.

来源：https://stackoverflow.com/questions/28755114/clr-dll-loaded-by-test-prog-but-not-by-calling-app

标签

c++

dll

interop