c#调用c++ dll传输struct array发生异常

Question

C++ header 定义:

#pragma once

#ifndef __AFXWIN_H__
#error "include 'stdafx.h' before including this file for PCH"
#endif

C++函数:

int Detect(Pos* pfps);

C++结构体定义:

struct FaceAngle
{
    int yaw;
    int pitch;
    int roll;
    float confidence;
};


typedef struct tagPOINT
{
    LONG x;
    LONG y;
}
POINT, * PPOINT, NEAR * NPPOINT, FAR * LPPOINT;


struct Pos
{
    RECT rcFace;
    POINT ptNose;
    FaceAngle fAngle;
    int nQuality;
    BYTE pFacialData[512];
    Pos()
    {
        memset(&rcFace, 0, sizeof(RECT));
        memset(&ptNose, 0, sizeof(POINT));
        memset(&fAngle, 0, sizeof(FaceAngle));
        nQuality = 0;
        memset(pFacialData, 0, 512);
    }
};

c++调用代码:

void detect()
{
    Pos ptfp[10];
    Detect(ptfp);
}

================================================== =============================

C# 函数定义:

[DllImport(THFaceDLLName, EntryPoint = "Detect")]
public static extern int Detect([In, Out] Pos[] posArray);

C# 结构体定义:

[System.Runtime.InteropServices.StructLayoutAttribute    (System.Runtime.InteropServices.LayoutKind.Sequential,
CharSet = System.Runtime.InteropServices.CharSet.Ansi, Pack = 1)]
public struct Pos
{
    public RECT rcFace;
    public POINT ptNose;
    public FaceAngle fAngle;
    int nQuality;
    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 512)]
    byte[] pFacialData;
};


[System.Runtime.InteropServices.StructLayoutAttribute    (System.Runtime.InteropServices.LayoutKind.Sequential, CharSet =     System.Runtime.InteropServices.CharSet.Ansi, Pack = 1)]
public struct RECT
{
    public int left;
    public int top;
    public int right;
    public int bottom;
}

[System.Runtime.InteropServices.StructLayoutAttribute    (System.Runtime.InteropServices.LayoutKind.Sequential, CharSet =     System.Runtime.InteropServices.CharSet.Ansi, Pack = 1)]
public struct POINT
{
    public int x;
    public int y;
}
[System.Runtime.InteropServices.StructLayoutAttribute    (System.Runtime.InteropServices.LayoutKind.Sequential, CharSet =     System.Runtime.InteropServices.CharSet.Ansi, Pack = 1)]
public struct FaceAngle
{
    int yaw;
    int pitch;
    int roll;
    float confidence;
};

C#调用代码:

void detect()
{
   Pos[] facePosArray = new Pos[10];
   int faceNum = Detect(facePosArray);
}

执行Detect函数后出现“System.AccessViolationException”异常，我应该将 Pos[] 转换为 Intptr 吗？谁能有好的解决方案

Answer 1

我找到了一个可以直接转换c++结构体的工具例如: Software Interface

这是下载地址: --download.microsoft.com/download/f/2/7/f279e71e-efb0-4155-873d-5554a0608523/CLRInsideOut2008_01.exe--