海康sdk中union结构体转换c#

[Talsha]

struct{
DWORD dwSize;
BYTE byStreamMode;
BYTE byRes1[3];
NET_DVR_DEC_STREAM_MODE uDecStreamMode;
BYTE byRes2[64];
}NET_DVR_PU_STREAM_CFG_V41,*LPNET_DVR_PU_STREAM_CFG_V41;

union{
NET_DVR_DEC_STREAM_DEV_EX struDecStreamDev;
NET_DVR_PU_STREAM_URL struUrlInfo;
NET_DVR_DEC_DDNS_DEV struDdnsDecInfo;
BYTE byRes[300];
}NET_DVR_DEC_STREAM_MODE,*LPNET_DVR_DEC_STREAM_MODE;

struct{
NET_DVR_STREAM_MEDIA_SERVER struStreamMediaSvrCfg;
NET_DVR_DEV_CHAN_INFO_EX struDevChanInfo;
}NET_DVR_DEC_STREAM_DEV_EX,*LPNET_DVR_DEC_STREAM_DEV_EX;

根据网上资料写的c#对应的

        [StructLayout(LayoutKind.Sequential)]
        public struct NET_DVR_PU_STREAM_CFG_V41
        {
            public uint dwSize;
           
            public byte byStreamMode;

            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 3, ArraySubType = UnmanagedType.I1)]
            public byte[] byRes1;
           
            public NET_DVR_DEC_STREAM_MODE uDecStreamMode;

            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 64, ArraySubType = UnmanagedType.I1)]
            public byte[] byRes2;

            public void Init()
            {
                byRes1=new byte[3];
                byRes2=new byte[64];
            }
        }

        [StructLayout(LayoutKind.Explicit,Size = 300)]
        public struct NET_DVR_DEC_STREAM_MODE
        {           
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 300, ArraySubType = UnmanagedType.I1)]
            [FieldOffsetAttribute(0)]
            public byte[] byRes;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct NET_DVR_DEC_STREAM_DEV_EX
        {
            public NET_DVR_STREAM_MEDIA_SERVER struStreamMediaSvrCfg;

            public NET_DVR_DEV_CHAN_INFO_EX struDevChanInfo;
        }

现在对NET_DVR_DEC_STREAM_DEV_EX中struDevChanInfo赋值后，准备进行StructToBytes转换为byte时程序挂掉（还未进入StructToBytes）。是不是我结构体有问题？？

[Talsha]

顶上去

[xuzuning]

你给的信息不足，无法判定你书写的是否合适
既然 C# 取消了联合，自然有其道理（实现上有难度）。硬要去模拟一个，显然不是稳妥的办法
其实借助 内存映射文件，就可轻松的实现结构的转换

[wanghui0380]

？？海康自己有完整的c# demo,干嘛还自己转

[xian_wwq]

struct对应翻译的时候，一定要注意字节对齐方式
StructLayout特性支持三种附加字段：
CharSet、Pack、Size。
某一项对不上都会导致DllImport失败

[拜一刀]

海康有全套c#吧
倒是vb用起来自己转好多东西.....