Question

我想将C＃方法挂钩到用C ++ DLL编写的C ++事件

C ++方面 #include

extern "C"
{
    typedef void (__stdcall *PFN_MYCALLBACK)();
    int __stdcall MyUnmanagedApi(PFN_MYCALLBACK callback);
}

C＃side

public delegate void MyCallback();
[DllImport("data_acquisition_sys.dll")]
public static extern void MyUnmanagedApi(MyCallback callback);

static void Main(string[] args) {

    MyUnmanagedApi(
    delegate()
    {
        Console.WriteLine("Called back by unmanaged side");
    }
    );
    }
}

我关注http://blogs.msdn.com/b/davidnotario/archive/2006/01/13/512436.aspx

错误

未处理的异常：System.EntryPointNotFoundException：无法在DLL“data_acquisition_sys.dll”中找到名为“MyUnmanagedApi”的入口点。 at the affect_detection_sys.Program.MyUnmanagedApi（MyCallback callback）at C：\ Users \ Public \ Docume
中的affect_detection_sys.Program.Main（String [] args）

Answer 1

对于所有感兴趣的各方，这是解决问题的有效方法。

C ++方

extern "C"
{
typedef void (*callback_function)();
callback_function gCBF;

__declspec(dllexport) void StartAcquisition(callback_function callback) {

    gCBF = callback;

    cout << "Acquisition started" << endl;
}

void DoWork() {
    gCBF()
}
}

C＃side

[DllImport("data_acquisition_sys.dll", EntryPoint = "StartAcquisition")]
    public static extern void StartAcquisition(MyCallback callback);
StartAcquisition(delegate()
{

    Console.WriteLine("Called back by unmanaged side ");
}
);

请注意，callback_function是一个空方法（），因为返回并接受任何数据会导致运行时崩溃。这已在其他主题中报道，但答案尚未给出。

Answer 2

MyUnmanagedApi返回int，您已声明void。试试这个：

public delegate void MyCallback();
[DllImport("data_acquisition_sys.dll")]
public static extern int MyUnmanagedApi(MyCallback callback);

static void Main(string[] args) {

    MyUnmanagedApi(
    delegate()
    {
        Console.WriteLine("Called back by unmanaged side");
    }
    );
    }
}

挂钩到C＃DLL事件表C＃

2 个答案: