Adding an unmanaged DLL

[ba.hons]

Hello,

wondering if somone could clear something up for me as i have been
reading around this subject for a while and am still confused.

I have a DLL from a hardware vendor but i dont know what language the
DLL is written in.

I would like to use this DLL from managed code (c#). From what i have
read i need this to be a COM object, but i dont really understand how
you differentiate between a dll written in C++ which is a COM object
and on that isnt.

Each time i try to add the dll as a reference (VS 2003 .Net 2.0) i get
the following message:

A reference to MYDLL.dll could not be added. This is not a valid
assembly or COM component.

I have tried using PINVOKE see code below and managed to call a
method from the DLL using my c# application but i dont really want to
write a method for each method the DLL supports, mainly becuase i am
worried about casting data types etc

[DllImport("MyDLL.dll", SetLastError = true, CharSet =
CharSet.Auto)]
static extern bool AlarmLogSize(int lpDirectoryName,
out uint lpFreeBytesAvailable);

Form1.AlarmLogSize(0, out freeBytesAvail);
MessageBox.Show(freeBytesAvail.ToString());

Can anyone tell me how best i can use this DLL and what my options
are.

Also i have an example application written in VB6 which come with the
DLL and that has a Module which seems looks like this:

Public Declare Function AlarmLogSize Lib "VertX.dll" (ByVal mode As
Long, _
logSize As Long) As Long

I have no idea when it comes to VB but i presume this is the
equivilent of what am doing with my PINVOKE applicaiton.

Any help really appreicated!

Thanks

Adam

[=?Utf-8?B?UGV0ZXIgQnJvbWJlcmcgW0MjIE1WUF0=?=]

The first thing you should do is determine whether this dll is indeed a COM
server. Attempt to register it with "regsvr32 yourdllpathandname".
Regsvr32.exe should be in your windows or system32 folder. If COM
registration succeeds, you should then be able to set a reference from Visual
Studio by switching to the COM tab in "add reference" and you should find
your COM server listed there.
Visual Studio will automatically generate a .NET Com Interop wrapper.
Peter

--
Site: http://www.eggheadcafe.com
UnBlog: http://petesbloggerama.blogspot.com
Short urls & more: http://ittyurl.net


"ba.hons" wrote:

Hello,

wondering if somone could clear something up for me as i have been
reading around this subject for a while and am still confused.

I have a DLL from a hardware vendor but i dont know what language the
DLL is written in.

I would like to use this DLL from managed code (c#). From what i have
read i need this to be a COM object, but i dont really understand how
you differentiate between a dll written in C++ which is a COM object
and on that isnt.

Each time i try to add the dll as a reference (VS 2003 .Net 2.0) i get
the following message:

A reference to MYDLL.dll could not be added. This is not a valid
assembly or COM component.

I have tried using PINVOKE see code below and managed to call a
method from the DLL using my c# application but i dont really want to
write a method for each method the DLL supports, mainly becuase i am
worried about casting data types etc

[DllImport("MyDLL.dll", SetLastError = true, CharSet =
CharSet.Auto)]
static extern bool AlarmLogSize(int lpDirectoryName,
out uint lpFreeBytesAvailable);

Form1.AlarmLogSize(0, out freeBytesAvail);
MessageBox.Show(freeBytesAvail.ToString());

Can anyone tell me how best i can use this DLL and what my options
are.

Also i have an example application written in VB6 which come with the
DLL and that has a Module which seems looks like this:

Public Declare Function AlarmLogSize Lib "VertX.dll" (ByVal mode As
Long, _
logSize As Long) As Long

I have no idea when it comes to VB but i presume this is the
equivilent of what am doing with my PINVOKE applicaiton.

Any help really appreicated!

Thanks

Adam