Trying to read a C dll and convert some code

[Bum]

Hello all,

I have a C dll I need to tap into and some C code to interpret to vb.net 2005, but am so far unsuccessful. I just get the generic "runtime has encountered a fatal error at XXXXXX memory". I think my prob is passing the variables. Also, I know the * refers to pointers, but not sure how to interpret them. Hope someone can help...

'Here is the C Code:

[CODE=c]enum XXXXStatus {StatusUnknown = 0,
Processed,
NoSuchSession,
NoSuchInfo,
ReadOnlyInfo,
InvalidInfo,
NotYetImplement ed = -1};

enum DataEncoding {EncodingUnknow n = 0,
NoValue,
ZeroTerminatedS tring,
Short16,
Int32,
Double64,
Boolean8,
Char8,
BinaryByte8
};

#define XXXX_INFO_ID_LE NGTH 32

struct XXXXSessionInfo Parameter {
char InfoID[XXXX_INFO_ID_LE NGTH];
int InfoValueLength ; /* Total bytes */
enum DataEncoding InfoEncoding;
int InfoDataCount; /* Number of values or elements */
void *InfoData;
};


struct XXXXSessionInfo Response {
enum XXXXStatus Status;
char InfoID[XXXX_INFO_ID_LE NGTH];
int InfoParameterCo unt;
struct XXXXSessionInfo Parameter *InfoParameterL ist;
};


struct XXXXSessionInfo Response __declspec (dllexport) *XXXXGetSession Info (unsigned long SessionID, char *InfoID);[/CODE]


'here's the call in C:

Info = XXXXGetSessionI nfo (SessionID, “SystemInventor y”)


'now here's what I have sofar in VB.net:

[CODE=vbnet]Public Enum DataEncoding
EncodingUnknown = 0
NoValue
ZeroTerminatedS tring
Short16
Int32
Double64
Boolean8
Char8
BinaryByte8
End Enum

Public Enum XXXXStatus
StatusUnknown = 0
Processed
NoSuchSession
NoSuchInfo
ReadOnlyInfo
InvalidInfo
RequestComplete
NotYetImplement ed = -1
End Enum

<DllImport("XXX Xapi.dll", EntryPoint:="XX XXGetSessionInf o", ExactSpelling:= False, CharSet:=CharSe t.Unicode)> _
Public Function XXXXGetSessionI nfo(ByVal SessionID As ULong, ByRef InfoID As String) As XXXXSessionInfo Response
End Function

Public Class XXXXSessionInfo Parameter
<MarshalAs(Unma nagedType.ByVal TStr, SizeConst:=32)> Public InfoID As String
Public InfoValueLength As Integer ' Total bytes
Public InfoEncoding As DataEncoding
Public InfoDataCount As Integer ' Number of values or elements
Public InfoData As IntPtr
End Class

Public Class XXXXSessionInfo Response
Public Status As XXXXStatus
<MarshalAs(Unma nagedType.ByVal TStr, SizeConst:=32)> Public InfoID As String
Public InfoParameterCo unt As Integer
Public InfoParameterLi st As XXXXSessionInfo Parameter
End Class[/CODE]

'heres the call I use in vb.net:

[CODE=vbnet]dim Info As XXXXSessionInfo Response

'please note sessionID was given in earlier code not shown
Info = XXXXGetSessionI nfo(SessionID, "SystemInventor y")[/CODE]

Thanks in advance! B