（最高难度）C#调用c++ DLL(返回结构数组指针) ，顶者有分!

[gyf19]

如何把返回c++结构数组指针，c#结构数组?? 请大侠帮助

c++定义：
QUERY* QueryTransactionHistory(DWORD dwIP,int nPort,TRANSACTION * ,int* outNum,int* nErrorCode);

TRANSACTION结构：
typedef struct TRANSACTION
{
char account[19];
int maxNum;
char startDate[16];
char endDate[16];
}TRANSACTION;

QUERY结构：
typedef struct QUERY
{
int id;
int itemAmount;
int gold;
int silver;
char itemName[30];
}QUERY;

[qqchen79]

这里是我的C++ DLL代码，和上面的C#测试过没有问题。
你得C++一边的代码是怎么实现的？

typedef struct TRANSACTION
{
char account[19];
int maxNum;
char startDate[16];
char endDate[16];
} TRANSACTION;

typedef struct QUERY
{
int id;
int itemAmount;
int gold;
int silver;
char itemName[30];
}QUERY;

extern "C" _declspec(dllexport) QUERY* QueryTransactionHistory(DWORD dwIP,int nPort,TRANSACTION * pTran, int* outNum,int* nErrorCode) {
cout << "dwIP = " << dwIP << ", nPort = " << nPort << ", pTran ->maxNum = " << pTran ->maxNum << endl;
cout << "pTran -> account = " << pTran ->account << ", pTran ->startDate = " << pTran ->startDate << ", pTran ->endDate = " << pTran ->endDate << endl;

QUERY* ret = (QUERY* )malloc(sizeof(QUERY) * 2);
ret[0].id = 0;
ret[0].gold = ret[0].silver = ret[0].itemAmount = 1;
strcpy(ret[0].itemName, "Item0");

ret[1].id = 1;
ret[1].gold = ret[1].silver = ret[1].itemAmount = 2;
strcpy(ret[1].itemName, "Item1");

(*outNum) = 2;
(*nErrorCode) = 0;
return ret;
}

[jiaguoli]

学习 顶！！

[yzqlee]

这种问题还是顶顶算了。

[blueice008]

顶

[lr21shiji]

佩服
顶

[cengyidao]

呵呵,顶~~

[leq_82]

帮顶

[penglewen]

up

[vabug]

确实不好搞,我前两天才搞好了C#与com互相传递IStream
帮顶

[OriesMap]

标记，留名。
顶一下，关注此问题。

[jxf654]

up

[gameboy766]

mark

[huheng_0_0]

mark

[honkerhero]

结构要用引用来传，因为在C++中它其实是一个指针

[angeldjd]

帮顶.

[newskycity]

有趣!

[gyf19]

qqchen79(知秋一叶) 方法可以用，现在结帖

[zj_newer]

帮忙顶，同时学习！

[tommir3]

为了看着方便，整理一下

 [StructLayout(LayoutKind.Sequential,   CharSet=CharSet.Ansi)] 
        public   class   TRANSACTION 
        { 
                [MarshalAs(UnmanagedType.ByValTStr,   SizeConst   =   19)] 
                public   string     account; 

                public   int   maxNum; 

                [MarshalAs(UnmanagedType.ByValTStr,   SizeConst   =   16)] 
                public   string   startDate; 

                [MarshalAs(UnmanagedType.ByValTStr,   SizeConst   =   16)] 
                public   string   endDate; 
        } 

        [StructLayout(LayoutKind.Sequential,   CharSet   =   CharSet.Ansi)] 
        public   class   QUERY 
        { 
                public   int   id; 
                public   int   itemAmount; 
                public   int   gold; 
                public   int   silver; 

                [MarshalAs(UnmanagedType.ByValTStr,   SizeConst   =   30)] 
                public   string   itemName; 
        } 

        class   Program 
        { 
                [DllImport( "CPPDLL.DLL ",   CallingConvention   =   CallingConvention.StdCall)] 
                public   extern   static   IntPtr   QueryTransactionHistory(uint   swIP,   int   nPort,   TRANSACTION   pTran,   out   int   cnt,   out   int   nErrCode); 

                static   void   Main(string[]   args) 
                { 
                        int   cnt,   errCode; 
                        TRANSACTION   tran   =   new   TRANSACTION(); 

                        tran.account         =   "account "; 
                        tran.endDate         =   "endDate "; 
                        tran.startDate     =   "startDate "; 
                        tran.maxNum           =   50; 

                        //get   retrun   value   as   IntPtr 
                        IntPtr   ptr   =   QueryTransactionHistory(0,   0,   tran,   out   cnt,   out   errCode); 
                        Console.WriteLine( "============   CS   =============== "); 
                        Console.WriteLine( "Count   =   {0},   errCode   =   {1} ",   cnt,   errCode); 

                        IntPtr   head   =   ptr; 
                        for   (int   i   =   0;   i   <   cnt;   ++i) 
                        { 
                                //extract   struct   from   pointer 
                                QUERY   q   =   (QUERY)Marshal.PtrToStructure(ptr,   typeof(QUERY)); 
                                Console.WriteLine( "id   =   {0},   gold   =   {1},   silver   =   {2},   itemAmount   =   {3},   itemName   =   {4} ", 
                                        q.id,   q.gold,   q.silver,   q.itemAmount,   q.itemName); 

                                //move   pointer   by   sizeof(QUERY)   to   the   next   one 
                                //WARNING:   assume   32   bit   machine!!!!!! 
                                ptr   =   (IntPtr)(ptr.ToInt32()   +   Marshal.SizeOf(typeof(QUERY))); 
                        } 
                        //TODO:   need   to   free   memory 
                } 
        }

typedef   struct   TRANSACTION 
{ 
char account[19]; 
int maxNum; 
char startDate[16]; 
char endDate[16]; 
}   TRANSACTION; 

typedef   struct   QUERY 
{ 
int id; 
int itemAmount; 
int gold; 
int silver; 
char itemName[30]; 
}QUERY; 

extern   "C "   _declspec(dllexport)   QUERY*   QueryTransactionHistory(DWORD   dwIP,int   nPort,TRANSACTION   *   pTran,   int*   outNum,int*   nErrorCode)   { 
cout   < <   "dwIP   =   "   < <   dwIP   < <   ",   nPort   =   "   < <   nPort   < <   ",   pTran   -> maxNum   =   "   < <   pTran   -> maxNum   < <   endl; 
cout   < <   "pTran   ->   account   =   "   < <   pTran   -> account   < <   ",   pTran   -> startDate   =   "   < <   pTran   -> startDate   < <   ",   pTran   -> endDate   =   "   < <   pTran   -> endDate   < <   endl; 

QUERY*   ret   =   (QUERY*   )malloc(sizeof(QUERY)   *   2); 
ret[0].id   =   0; 
ret[0].gold   =   ret[0].silver   =   ret[0].itemAmount   =   1; 
strcpy(ret[0].itemName,   "Item0 "); 

ret[1].id   =   1; 
ret[1].gold   =   ret[1].silver   =   ret[1].itemAmount   =   2; 
strcpy(ret[1].itemName,   "Item1 "); 

(*outNum)   =   2; 
(*nErrorCode)   =   0; 
return   ret; 
} 

[laneagle]

楼主要说话算话啊！