下面是我的c++ DLL
// DLL.cpp : Defines the exported functions for the DLL application.
#include "stdafx.h"
//#include <stdexcept>
#include<iostream>
using namespace std;
typedef void (*FunctionPtr)(int);
void (*FunctionPtr1)(int);
extern "C" __declspec(dllexport)void Caller();
extern "C" __declspec(dllexport)void RegisterFunction(FunctionPtr func_ptr);
extern void Caller()
{
int i = 10;
FunctionPtr1(i);
}
extern void RegisterFunction(FunctionPtr func_ptr1)
{
FunctionPtr1 = func_ptr1;
}
此 DLL 将从 c# 获取对函数名称的引用,并将参数传递给 c# 函数。 这是我的 C# 代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
namespace test
{
class Program
{
[DllImport("C:/Users/10602857/Documents/Visual Studio 2010/Projects/DLL/Debug/DLL.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern void Caller();
[DllImport("C:/Users/10602857/Documents/Visual Studio 2010/Projects/DLL/Debug/DLL.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern fPointer RegisterFunction(fPointer aa);
static void Main(string[] args)
{
Console.WriteLine("DLL Linking");
fPointer abc = new fPointer(ping);
RegisterFunction(abc); //send address of function to DLL
Caller(); //call from DLL
}
public delegate void fPointer(int s); // point to every functions that it has void as return value and with no input parameter
public static void ping(int a)
{
Console.WriteLine("ping executed " + a);
}
public static void add1()
{
Console.WriteLine("add executed");
}
}
}
c# 代码能够获取我在 c++ dll 中 paseed 的值,如下所示
int i = 10;
FunctionPtr1(i);
M 获得了 sedired 输出,但程序在执行后崩溃了
Unhandled Exception: System.AccessViolationException: Attempted to read or write
protected memory. This is often an indication that other memory is corrupt.
at test.Program.Caller()
为什么我会收到这个??
最佳答案
好的,我给你写了测试代码。 概念很简单。
您使用 C++ 或 C 编写了 dll。
CLR 库(托管 dll)包装您的 dll。
您的 C# 代码可以通过 CLR 库使用您的 native DLL。
您的 native DLL
MyDll.cpp
#include "stdafx.h"
#include<iostream>
using namespace std;
typedef void (*FunctionPtr)(int);
void (*FunctionPtr1)(int);
extern "C" __declspec(dllexport)void Caller();
extern "C" __declspec(dllexport)void RegisterFunction(FunctionPtr func_ptr);
extern void Caller()
{
int i = 10;
FunctionPtr1(i);
}
extern void RegisterFunction(FunctionPtr func_ptr1)
{
FunctionPtr1 = func_ptr1;
}
您的 CLR 库, native Dll 的包装器
MyDllCLR.h
#pragma once
using namespace System;
using namespace System::Runtime::InteropServices;
typedef void (*FunctionPtr2)(int);
extern "C" __declspec(dllimport)void Caller();
extern "C" __declspec(dllimport)void RegisterFunction(FunctionPtr2 func_ptr);
namespace MyDllCLR {
void MyFunc(int i);
public ref class Class
{
public:
delegate void FunctionDelegate(int i);
static FunctionDelegate^ fun;
static void Caller1()
{
Caller();
}
static void RegisterFunction1(FunctionDelegate^ f)
{
fun = f; // Wrapper MyFunc call this delegate
// this occurs runtime error and I don't know why.
// So I wrote Warpper MyFunc() method. I usually do like this.
//IntPtr p = Marshal::GetFunctionPointerForDelegate(fun);
//RegisterFunction((FunctionPtr2)(void*)p);
// Register Function Wrapper instead of user delegate.
RegisterFunction(MyFunc);
}
};
}
MyDllCLR.cpp
#include "stdafx.h"
#include "MyDllCLR.h"
void MyDllCLR::MyFunc(int i)
{
MyDllCLR::Class::fun(i);
}
使用 native DLL 的 C# 代码
Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace TestMyDllCLR
{
class Program
{
static void MyFunc(int i)
{
Console.WriteLine("Come on! {0}", i);
}
static void Main(string[] args)
{
MyDllCLR.Class.RegisterFunction1(MyFunc);
MyDllCLR.Class.Caller1();
}
}
}
Program.cs 需要 Native DLL 和 CLR DLL
当然,这不是实现您目标的唯一方法。 :)
关于c# - 未处理的异常 : System. AccessViolationException:尝试读取或写入,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/12509252/