vc函数定义如下
typedef struct _GroupCard
{
DWORD cardNo;
WORD reserved;
WORD wCardCount;
_GroupCard * pNext; //pointer to the next group card.
} TGroupCard, *PGroupCard; int GetCardReg(BYTE ComPort, BYTE CtrlID, WORD Offset, WORD GroupCount, WORD *GroupCountGet, TGroupCard *lpGroupCard); 我想在c#中调用,应该怎么写接口函数?
typedef struct _GroupCard
{
DWORD cardNo;
WORD reserved;
WORD wCardCount;
_GroupCard * pNext; //pointer to the next group card.
} TGroupCard, *PGroupCard; int GetCardReg(BYTE ComPort, BYTE CtrlID, WORD Offset, WORD GroupCount, WORD *GroupCountGet, TGroupCard *lpGroupCard); 我想在c#中调用,应该怎么写接口函数?
{
public uint cardNo;
public ushort reserved;
public ushort wCardCount;
public GroupCard* pNext; //或者 public IntPtr pNext
}int GetCardReg(byte ComPort, byte CtrlID, ushort Offset, ushort GroupCount,ref ushort GroupCountGet, ref GroupCard lpGroupCard);
或者
unsafe int GetCardReg(byte ComPort, byte CtrlID, ushort Offset, ushort GroupCount,ref ushort GroupCountGet, GroupCard* lpGroupCard);
[StructLayout(LayoutKind.Sequential)]
class TGroupCard
{
public int cardNo;
public ushort reserved;
public ushort wCardCount;
public TGroupCard pNext; //pointer to the next group card.
} TGroupCard PGroupCard;
int GetCardReg(byte ComPort, byte CtrlID, ushort Offset, ushort GroupCount, ref ushort GroupCountGet, ref TGroupCard lpGroupCard);
unsafe int GetCardReg(byte ComPort, byte CtrlID, ushort Offset, ushort GroupCount,ref ushort GroupCountGet, GroupCard* lpGroupCard);如下:
GroupCard* lpGroupCard =null;
ushort GroupCountGet=0;
GetCardReg(3,1,0,3,ref GroupCountGet,lpGroupCard );
能够执行,但lpGroupCard的值为零,不知为什么
int GetCardReg(byte ComPort, byte CtrlID, ushort Offset, ushort GroupCount,ref ushort GroupCountGet, ref GroupCard lpGroupCard);按如下方式调用:
int i=0;
...
i=4;
...
GroupCard lpGroupCard = new GroupCard ();
ushort GroupCountGet=0;
GetCardReg(3,1,0,3,ref GroupCountGet,ref lpGroupCard ); lpGroupCard 倒是取出值了,但取值是否正确我也不知道,因为我我知道原始值是多少。
但是这有个奇怪的问题;如上面所写,我在最开始定义了一个变量i,但是当调用了这个函数后i却无缘无故地变了?这是什么原因?
请大家再指点一下