C # managed code and C + + unmanaged code are called one another (C # calls C + + code &.net code security)

In recent projects, project source code confidentiality issues are involved, because the code is written in C #, easy to decompile, so the decision to extract the core algorithm part of the use of C + + writing, C + + so far seems to have not been very good decompile, of course, if you are a disassembly master, perhaps it is possible to decompile. This means that C # managed code and C + + unmanaged code call each other, and then we investigate some of the information and share

A. Static call C + + dynamic link in C #

1. VC Project Cppdemo, the establishment of the time to select Win32 Console (DLL), select the DLL.

2. Add the code to the DllDemo.cpp file.

extern "C" __declspec(dllexport) int Add(int a,int b)
{

　　　　 return a+b;
}

3. Compile the project.

4. Create a new C # project, select Console application, set up test program Interopdemo

5. Add references in Program.cs: using System.Runtime.InteropServices;

6. Add the following code to the Pulic class program:

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

namespace InteropDemo
{
　　　 class Program
　　　 {
　　　　　　　 [DllImport("CppDemo.dll", EntryPoint = "Add", ExactSpelling = false, CallingConvention = CallingConvention.Cdecl)]
　　　　　　　 public static extern int Add(int a, int b); //DllImport请参照MSDN

　　　　　　　 static void Main(string[] args)
　　　　　　　 {
　　　　　　　　　　　 Console.WriteLine(Add(1, 2));
　　　　　　　　　　　 Console.Read();
　　　　　　　 }
　　　 }
}

OK, now you can test the add program, it is not possible to call the C + + dynamic link in C #, of course, this is a static call, you need to Cppdemo compiled the generated DLL in the Dlldemo program's Bin directory