import unmanaged dll into c sharp

[rorybr]

hi,
i'm trying to import an unmanaged dll into a c# application. The dll is given to me but i'm new with dll import thing and having some troubles importing it. Dll comes with a pdf file which describes the functions but all parameters and types are c++ type and i need to write them as c# types. i tried "Dllimport" but i think i couldn't write the correct parameter types. Functions use handles and pointers which doesn't make it easier for me. If someone can write the correct syntax and usage of the functions, i will be most grateful. im writing the functions as described in the pdf:

Comm_Init function: Initializes the DLL for first time loading. Gets a window handle (HWND) as
parameter.

void Comm_init
(
HWND wndHandle
);

Comm_create function: creates a TCP communication to device using ip address and TCP port number.

TCommHnd Comm_create
(
char *address,
int port,
mEventHandler eventHandler,
int synchComm
);
 

these are the main functions i need to figure out. And there is a type definition (TCommHnd) which described as "typedef void* TCommHnd;" .

Comm_init function initializes DLL, for further usage. It is not a thread safe
function, it should be called one time during the operation of the DLL. All functions except
Comm_init are thread safe functions, for different TCommHnd’s.

I wrote the type definitions and functions into a class file in my project and tried to use the functions in the program. But i think i made some mistakes either in definitions or in usage. I dont really know anything about dllimport and handles but i really need to figure this one out. should i use LoadLibrary and GetProcAddress? Any help will be appreciated,

Best regards

[tlhintoq]

TIP: When you first created your question you were asked to wrap your code with [code] tags.

It really does help a bunch. Look how much easier it is to read now that someone has done it for you. Its the button with a '#' on it. More on tags. They're cool. Check'em out.

[tlhintoq]

Are you using this DLL because you need *other* functions as well, or because you thought it would be an easy shortcut to TCP/IP communication?

If you don't need other functions that are in the DLL, it might be a lot cleaner for your application to just to TCP/IP within C#

There is an exampel TCP client/server on the MSDN
http://code.msdn.microsoft.com/tcpclientandserverEx

[rorybr]

I'm using this dll because i need to use other functions of the dll... dll is not just a TCP/IP dll... it creates modbusTCP/IP communication with some specific devices... thats why i have to use it