谁能帮我解释一下这个结构体呀！

[fangzhizhou08]

谢谢各位了！
struct RMSG //用于传送消息
{
union
{
unsigned long Head;
struct
{
unsigned char MsgType; //消息类型
unsigned char BoardFlag; //板类型标志(见FLAGXXX定义)
// unsigned char FuncFlag;
union
{
unsigned char BoardIndex
struct
{
unsigned char nBoardNo:4;
unsigned char nBoxNo:4;
};
};
union
{
struct
{
unsigned char nResCh:5;
unsigned char nResNo:3;
};
struct
{
unsigned char nCH64:6;
unsigned char nDSP4:2;
};
unsigned char nBoardCh;
};
};

};

union
{
unsigned long Param; //长参数
struct
{
short ShortParam; //短参数
unsigned short LogicCh;
};
struct
{
unsigned char Msg1Len; //消息内容(Data1)长度(0--15)
unsigned char Msg2Len; //消息内容(Data2)长度(0--15)
};
struct
{
unsigned char MsgLen; //消息内容(Data)长度(0--32)
unsigned char SubMsgType; //子消息类型
};
struct
{
unsigned short nCTBus; // CT 总线号
unsigned short nCTCh; // 单根 CT总线中CT 通道号
};
struct
{
union{
struct
{
unsigned char nLocalBus:3; //
unsigned char nLocalCh; //
};
struct
{
unsigned char nResType;
unsigned char nResNo;
};
unsigned char nBoardCh;
}L;
};
};

union
{
struct
{
unsigned char Data1[16];
unsigned char Data2[16];
};
struct
{
unsigned short Data1w[8];
unsigned short Data2w[8];
};
unsigned char Data[32];
unsigned short Dataw[16];
unsigned int Datai[8];
float Dataf[8];
tagResAssign ResAssign;
tagFaxStatus data;
};
};

[archer_hao]

呵呵,兄弟是在写和继电保护有关的系统么?

你只需要搞清楚,在struct中是一个个成员接起来存放,在union中是所有成员共享一段内存就好了

[wangweixing2000]

看看msdn就好了

[afantict]

这个很简单
怎么讲