Marhsalling a structure

[=?ISO-8859-1?Q?Marc-Aur=E8le_Brothier?=]

Hi,

I have a DLL in C++ that I want to use in my C# program on my PocketPC
2003. The DLL first creates the structure and initializes the structure,
I have not problem to get the structure back in my C# program. But when
I pass this structure as an argument in a function, I got an error:

"NotSupportedException"


I will be glad if someone can help me. I read a lof of different post
about Marshalling but didn't find the answer.

/Marco

------------------------------
Here is the C++ code:

typedef struct _ADAPTER {
UINT nWrites;
HANDLE hFile;
HANDLE ReadEvent;
} ADAPTER, *LPADAPTER;

LPADAPTER PacketOpenAdapter(LPTSTR AdapterName);

BOOLEAN PacketSetHwFilter(LPADAPTER AdapterObject,ULONG Filter);

------------------------------
Here is the C# code:

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct ADAPTER
{
public uint nWrites;
public IntPtr hFile;
public IntPtr ReadEvent;
}

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketOpenAdapter" ) ]
private static extern IntPtr DllPacketOpenAdapter(String sb);

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketSetHwFilter" ) ]
private static extern bool DllPacketSetHwFilter(ref IntPtr pHandle,
ulong filter);


public bool OpenAdapter(string name)
{
IntPtr tmp = DllPacketOpenAdapter(name);
adapterHandle = (Packet32.ADAPTER)Marshal.PtrToStructure(tmp,
typeof(Packet32.ADAPTER));
if (adapterHandle.hFile != IntPtr.Zero)
{
adapterName = name;
return true;
}
return false;
}


public bool SetHwFilter(ulong filter)
{
IntPtr tmp;
int sizeStruct = Marshal.SizeOf(typeof(Packet32.ADAPTER));
tmp = LocalAlloc(MemoryAllocFlags.LPTR,
(uint)Marshal.SizeOf(typeof(Packet32.ADAPTER)));
try
{
Marshal.StructureToPtr(adapterHandle, tmp, false);
bool res = DllPacketSetHwFilter(ref tmp, filter);
Marshal.PtrToStructure(tmp, adapterHandle);
LocalFree(tmp);
return res;
}
catch(Exception e) {
string msg = e.Message;
LocalFree(tmp);
}
return false;
}

 

[Alex Yakhnin [MVP]]

Try to change:
private static extern bool DllPacketSetHwFilter(ref IntPtr
pHandle,
ulong filter);

to:

private static extern bool DllPacketSetHwFilter(IntPtr
pHandle, uint filter);

HTH... Alex

 

[=?ISO-8859-1?Q?Marc-Aur=E8le_Brothier?=]

Hi,

Thank you very much, it's working.
Why the ulong doesn't work? (I tried first without this modification)

Many thanks
/Marco

Try to change:
private static extern bool DllPacketSetHwFilter(ref IntPtr
pHandle,
ulong filter);

to:

private static extern bool DllPacketSetHwFilter(IntPtr
pHandle, uint filter);

HTH... Alex

-----Original Message-----
Hi,

I have a DLL in C++ that I want to use in my C# program

on my PocketPC

2003. The DLL first creates the structure and initializes

the structure,

I have not problem to get the structure back in my C#

program. But when

I pass this structure as an argument in a function, I got

an error:

"NotSupportedException"


I will be glad if someone can help me. I read a lof of

different post

about Marshalling but didn't find the answer.

/Marco

------------------------------
Here is the C++ code:

typedef struct _ADAPTER {
UINT nWrites;
HANDLE hFile;
HANDLE ReadEvent;
} ADAPTER, *LPADAPTER;

LPADAPTER PacketOpenAdapter(LPTSTR AdapterName);

BOOLEAN PacketSetHwFilter(LPADAPTER AdapterObject,ULONG
Filter);

------------------------------
Here is the C# code:

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct ADAPTER
{
public uint nWrites;
public IntPtr hFile;
public IntPtr ReadEvent;
}

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketOpenAdapter" ) ]
private static extern IntPtr DllPacketOpenAdapter(String
sb);

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketSetHwFilter" ) ]
private static extern bool DllPacketSetHwFilter(ref

IntPtr pHandle,

ulong filter);


public bool OpenAdapter(string name)
{
IntPtr tmp = DllPacketOpenAdapter(name);
adapterHandle = (Packet32.ADAPTER)
Marshal.PtrToStructure(tmp,

typeof(Packet32.ADAPTER));
if (adapterHandle.hFile != IntPtr.Zero)
{
adapterName = name;
return true;
}
return false;
}


public bool SetHwFilter(ulong filter)
{
IntPtr tmp;
int sizeStruct = Marshal.SizeOf(typeof
(Packet32.ADAPTER));

tmp = LocalAlloc(MemoryAllocFlags.LPTR,
(uint)Marshal.SizeOf(typeof(Packet32.ADAPTER)));
try
{
Marshal.StructureToPtr(adapterHandle, tmp,
false);

bool res = DllPacketSetHwFilter(ref tmp,
filter);

Marshal.PtrToStructure(tmp, adapterHandle);
LocalFree(tmp);
return res;
}
catch(Exception e) {
string msg = e.Message;
LocalFree(tmp);
}
return false;
}

.

 

[Paul G. Tobey [eMVP]]

ulong is 64 bits in the .NET environment.

Paul T.

Hi,

Thank you very much, it's working.
Why the ulong doesn't work? (I tried first without this modification)

Many thanks
/Marco

Try to change:
private static extern bool DllPacketSetHwFilter(ref IntPtr
pHandle,
ulong filter);

to:

private static extern bool DllPacketSetHwFilter(IntPtr
pHandle, uint filter);

HTH... Alex

-----Original Message-----
Hi,

I have a DLL in C++ that I want to use in my C# program

on my PocketPC

2003. The DLL first creates the structure and initializes

the structure,

I have not problem to get the structure back in my C#

program. But when

I pass this structure as an argument in a function, I got

an error:

"NotSupportedException"


I will be glad if someone can help me. I read a lof of

different post

about Marshalling but didn't find the answer.

/Marco

------------------------------
Here is the C++ code:

typedef struct _ADAPTER {
UINT nWrites;
HANDLE hFile;
HANDLE ReadEvent;
} ADAPTER, *LPADAPTER;

LPADAPTER PacketOpenAdapter(LPTSTR AdapterName);

BOOLEAN PacketSetHwFilter(LPADAPTER AdapterObject,ULONG
Filter);

------------------------------
Here is the C# code:

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct ADAPTER
{
public uint nWrites;
public IntPtr hFile;
public IntPtr ReadEvent;
}

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketOpenAdapter" ) ]
private static extern IntPtr DllPacketOpenAdapter(String
sb);

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketSetHwFilter" ) ]
private static extern bool DllPacketSetHwFilter(ref

IntPtr pHandle,

ulong filter);


public bool OpenAdapter(string name)
{
IntPtr tmp = DllPacketOpenAdapter(name);
adapterHandle = (Packet32.ADAPTER)
Marshal.PtrToStructure(tmp,

typeof(Packet32.ADAPTER));
if (adapterHandle.hFile != IntPtr.Zero)
{
adapterName = name;
return true;
}
return false;
}


public bool SetHwFilter(ulong filter)
{
IntPtr tmp;
int sizeStruct = Marshal.SizeOf(typeof
(Packet32.ADAPTER));

tmp = LocalAlloc(MemoryAllocFlags.LPTR,
(uint)Marshal.SizeOf(typeof(Packet32.ADAPTER)));
try
{
Marshal.StructureToPtr(adapterHandle, tmp,
false);

bool res = DllPacketSetHwFilter(ref tmp,
filter);

Marshal.PtrToStructure(tmp, adapterHandle);
LocalFree(tmp);
return res;
}
catch(Exception e) {
string msg = e.Message;
LocalFree(tmp);
}
return false;
}

.

 

[Geoff Schwab [MSFT]]

Hi Marco,

The following FAQ link has some good information on this exception and even
refers to your exact problem. This may be useful for future reference for
you.

6.15. Why do I get a MissingMethodException when I call a function from a
native DLL?
http://msdn.microsoft.com/mobility/prodtechinfo/devtools/netcf/faq/default.aspx#6.15

--
Geoff Schwab
Program Manager
Excell Data Corporation
http://msdn.com/mobility
http://msdn.microsoft.com/mobility/prodtechinfo/devtools/netcf/FAQ/default.aspx

This posting is provided "AS IS" with no warranties, and confers no rights.

Hi,

Thank you very much, it's working.
Why the ulong doesn't work? (I tried first without this modification)

Many thanks
/Marco

Try to change:
private static extern bool DllPacketSetHwFilter(ref IntPtr
pHandle,
ulong filter);

to:

private static extern bool DllPacketSetHwFilter(IntPtr
pHandle, uint filter);

HTH... Alex

-----Original Message-----
Hi,

I have a DLL in C++ that I want to use in my C# program

on my PocketPC

2003. The DLL first creates the structure and initializes

the structure,

I have not problem to get the structure back in my C#

program. But when

I pass this structure as an argument in a function, I got

an error:

"NotSupportedException"


I will be glad if someone can help me. I read a lof of

different post

about Marshalling but didn't find the answer.

/Marco

------------------------------
Here is the C++ code:

typedef struct _ADAPTER {
UINT nWrites;
HANDLE hFile;
HANDLE ReadEvent;
} ADAPTER, *LPADAPTER;

LPADAPTER PacketOpenAdapter(LPTSTR AdapterName);

BOOLEAN PacketSetHwFilter(LPADAPTER AdapterObject,ULONG
Filter);

------------------------------
Here is the C# code:

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct ADAPTER
{
public uint nWrites;
public IntPtr hFile;
public IntPtr ReadEvent;
}

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketOpenAdapter" ) ]
private static extern IntPtr DllPacketOpenAdapter(String
sb);

[ DllImport( "Packet32.dll", SetLastError=true,
EntryPoint="PacketSetHwFilter" ) ]
private static extern bool DllPacketSetHwFilter(ref

IntPtr pHandle,

ulong filter);


public bool OpenAdapter(string name)
{
IntPtr tmp = DllPacketOpenAdapter(name);
adapterHandle = (Packet32.ADAPTER)
Marshal.PtrToStructure(tmp,

typeof(Packet32.ADAPTER));
if (adapterHandle.hFile != IntPtr.Zero)
{
adapterName = name;
return true;
}
return false;
}


public bool SetHwFilter(ulong filter)
{
IntPtr tmp;
int sizeStruct = Marshal.SizeOf(typeof
(Packet32.ADAPTER));

tmp = LocalAlloc(MemoryAllocFlags.LPTR,
(uint)Marshal.SizeOf(typeof(Packet32.ADAPTER)));
try
{
Marshal.StructureToPtr(adapterHandle, tmp,
false);

bool res = DllPacketSetHwFilter(ref tmp,
filter);

Marshal.PtrToStructure(tmp, adapterHandle);
LocalFree(tmp);
return res;
}
catch(Exception e) {
string msg = e.Message;
LocalFree(tmp);
}
return false;
}

.

 

[poonamk]

Hi,
I am trying to add wrapper over functions exported by packet.dll. The implementation in this thread give me a start for the .Net C# implementation.
source code:

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct ADAPTER
{
public uint nWrites; //int NumWrites
public IntPtr hFile; //HANDLE hFile
public IntPtr ReadEvent;//HANDLE ReadEvent
}

[StructLayoutAttribute(LayoutKind.Sequential)]
public struct PACKET
{
public IntPtr hEvent; //HANDLE hEvent
public String Buffer;
public uint nLength; //UINT Length
public uint uBytesReceived; //DWORD ulBytesReceived
public bool bIoComplete; //BOOLEAN bIoComplete
}

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketOpenAdapter" ) ]
public static extern IntPtr DllPacketOpenAdapter(String sb);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketCloseAdapter" ) ]
public static extern void DllPacketCloseAdapter(ref IntPtr pHandle);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketSetHwFilter" ) ]
public static extern bool DllPacketSetHwFilter(ref IntPtr pHandle,uint filter);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketSetBuff" ) ]
public static extern bool DllPacketSetBuff(ref IntPtr pHandle,int buffsize);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketSetReadTimeout" ) ]
public static extern bool DllPacketSetReadTimeout(ref IntPtr pHandle,int timeOut);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketAllocatePacket" ) ]
public static extern IntPtr DllPacketAllocatePacket();

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketInitPacket" ) ]
public static extern void DllPacketInitPacket(ref IntPtr pHandle, ref String buffer,uint length);

[ DllImport( "Packet.dll", SetLastError=true,EntryPoint="PacketReceivePacket" ) ]
public static extern bool DllPacketReceivePacket(ref IntPtr pHandle, ref IntPtr pPacket, bool sync);

- following function calls have no issue:
DllPacketOpenAdapter and DllPacketSetHwFilter ( returns true)
-but call to DllPacketSetBuff does not return.

are there any issues with marshalling ?
Thanks in advance.