初学者 用VB调用VC写的动态链接库

#include<string.h>
#include<stdio.h>

typedef struct _TAG_Info
{
    char tagMac[64];
    char tagCoordinate[32];
}TAG_INFO;


typedef struct _RSSI_Info
{
    short nRSSI;
    char strCoordinate[32];
}RSSI_INFO;
TAG_INFO result;


extern"C" _declspec(dllexport) TAG_INFO _stdcall GetCoordinateByTagsRssi(char tagMac[64],short inAPCount,RSSI_INFO*pRssiInfo)//主要问题就是最后这个结构体指针不知道该怎么弄
{
    sprintf(result.tagCoordinate,"x:%f,y:%f",10.0,10.0);//这里没有写出算法 只要调用没问题 接口正确 
    strcpy(result.tagMac,tagMac);                       //就能输出x=10.0，y=10.0
        return result;
}

Private Type TAG_INFO
tagMac As String
tagCoordinate As String
End Type

Private Type RSSI_INFO
nRSSI As Integer
strCoordinate As String
End Type

Private Declare Function GetCoordinateByTagsRssi Lib "E:\blankDLL\Debug\DLL.dll" Alias "_GetCoordinateByTagsRssi@12" (ByVal tagMac As String, ByVal inAPCount As Integer, ByVal pRssiInfo As RSSI_INFO) As TAG_INFO
Private Sub Form_Load()
Dim mac As String
Dim ap As Integer
Dim test(1 To 10) As RSSI_INFO
test(1).nRSSI = 1
test(1).strCoordinate = "x:0,y:5"
test(2).nRSSI = 2
test(2).strCoordinate = "x:5,y:5"
test(3).nRSSI = 3
test(3).strCoordinate = "x:10,y:5"
test(4).nRSSI = 4
test(4).strCoordinate = "x:5,y:10"
Dim result_test As TAG_INFO

result_test = GetCoordinateByTagsRssi(mac, ap, varptr(test(1)))'总说这里的数据类型有问题
Form1.Show
Print result_test.tagMac
Print result_test.tagCoordinate

GetCoordinateByTagsRssi(char tagMac[64]
//不确定 VC 中定长数组参数怎么传，很可能直接将数组内容都压栈了，要改为
GetCoordinateByTagsRssi(char* tagMac

------解决方案--------------------

改一下： 
 Private Declare Function GetCoordinateByTagsRssi Lib  "E:\blankDLL\Debug\DLL.dll " Alias  "_GetCoordinateByTagsRssi@12 " (ByVal tagMac As Long, ByVal inAPCount As Long, ByRef pRssiInfo As RSSI_INFO) As TAG_INFO 

 第一个参数：字符数组，可以传字符串指针； 
 第二个参数：短整型，也要声明成Long； 
 第三个参数：结构结构指针，声明成ByRef 

 调用：result_test = GetCoordinateByTagsRssi(VarPtr(ByVal mac), ap, test(1)) 
 说明一下：VarPtr(ByVal mac)=StrPtr(mac)

------解决方案--------------------