ATL / WTL / STL Discussion Boards

Re: How To Add a Dll TO MFC Application in visual Studio

Member 1347149317-Oct-17 22:29

17-Oct-17 22:29

you mean that i have loaded .dll file correctly and the error is because of somewhat like syntax error?
but i have exactly copied the name of function in dll.
i dont know why this error occurs

Re: How To Add a Dll TO MFC Application in visual Studio

Richard MacCutchan17-Oct-17 22:45

Richard MacCutchan

17-Oct-17 22:45

I have no idea why the error occurred, beyond saying that is is caused by a bad address reference somewhere. And the only way to find out where it occurred is by using the debugger. Are you certain that the parameter 0x01 that you send to the ConnectByAddress function is valid? Check the documentation to see what that function is supposed to do, and what it is supposed to return.

Re: How To Add a Dll TO MFC Application in visual Studio

Jochen Arndt17-Oct-17 22:44

Jochen Arndt

17-Oct-17 22:44

To use functions from a DLL you have two choices: Early and late binding.

Early binding:
Link your application with the DLL by using the #import directive in one file (usually a source file using functions from the DLL) specifying the file name (usually without extension or with .lib), or add the .lib file to your project settings (Linker - Input).
Include the header file and call the functions defined in that file.

Late binding:
This is only necessary if the DLL might not be present when your application is executed or you do not have a .lib file. Then use LoadLibrary and GetProcAddress like in your above example. But check both return values to be not NULL. Have a look at the header file (if present), to know how to define the function prototypes. Example:

C++

typedef int (__stdcall *ConnectByAddressfuncPtr)(short Addr); 

ConnectByAddressfuncPtr LibMainConnectByAddress = NULL;
HMODULE hLib = LoadLibrary(_T("mcl_gen.dll"));
if (hLib)
    LibMainConnectByAddress = (ConnectByAddressfuncPtr)GetProcAddress(hLib,"ConnectByAddress");
if (LibMainConnectByAddress)
    LibMainConnectByAddress(0x01);

Note that I have initialised the function pointer with NULL and checked it before calling the function. Note also the __stdcall in the prototype declaration. It defines the calling convention used by the DLL. You have to check which is used (by inspecting the header file or asking the provider). __stdcall is common but it might be also __cdecl.

Re: How To Add a Dll TO MFC Application in visual Studio

Member 1347149317-Oct-17 23:13

Member 13471493

17-Oct-17 23:13

Hi. thank you for your answer. i dont have any .lib file

i tried your code but "LibMainConnectByAddress" still remains NULL. so the code skips
LibMainConnectByAddress(0x01);

do you know why?

thank you again

Re: How To Add a Dll TO MFC Application in visual Studio

Jochen Arndt17-Oct-17 23:29

Jochen Arndt

17-Oct-17 23:29

All I can suggest is to check if the DLL exports the function "ConnectByAddress" (e.g. using the Dependency Walker (depends.exe) Home Page[^] or executing dumpbin /exports path_to_dll on the command line; dumpbin is in the VC/bin folder) and trying it with different calling conventions like __cdecl.

I would use the Dependency Walker because it shows also the calling convention for the exported functions.

Re: How To Add a Dll TO MFC Application in visual Studio

Richard MacCutchan18-Oct-17 0:16

Richard MacCutchan

18-Oct-17 0:16

Member 13471493 wrote:
"LibMainConnectByAddress" still remains NULL.

You omitted to mention that in your reply to me. If that function pointer is null then it will cause the error you have seen. You need to check the function name that you are trying to get the address for, does it actually exist in the dll?

Re: How To Add a Dll TO MFC Application in visual Studio

Member 1347149318-Oct-17 0:58

Member 13471493

18-Oct-17 0:58

Yes it Does. i tried others functions that exist in dll too. but i got the same error. i am sure about syntax and existence of these functions in the dll.

Re: How To Add a Dll TO MFC Application in visual Studio

Richard MacCutchan18-Oct-17 1:18

Richard MacCutchan

18-Oct-17 1:18

But are you sure that the value you are sending to the function is correct?

Re: How To Add a Dll TO MFC Application in visual Studio

Jochen Arndt18-Oct-17 1:40

Jochen Arndt

18-Oct-17 1:40

Have you used the Dependency Walker or dumpbin meanwhile?

The exported names may be mangled (see Name mangling - Wikipedia[^] ). Then you have to pass the mangled name to GetProcAddress.

Re: How To Add a Dll TO MFC Application in visual Studio

Michael Haephrati22-Oct-17 2:22

Michael Haephrati

22-Oct-17 2:22

This article explains it. Basically you use LoadLibrary with the DLL's path given to it. The rest is mapping the functions you will need to call.

- Michael Haephrati מיכאל האפרתי

using /clr switch for ATL application raises an exception when the application is terminating.

Vijjuuu.23-Aug-17 0:00

Vijjuuu.

23-Aug-17 0:00

Hi,

i have created a sample ATL application in VS2010, added ATL Simple object.

it has only one method

int getVal()
{
return 10;
}

i have enabled /clr switch in the project properties and build in release mode. (i have added /clr because i want to consume some objects build in C#.net)

after registering the dll, i have consumed the COM object in vbscript. (the code below)

dim obj
set obj = createobject("MySample.COMSample")
msgbox obj.getVal()
set obj = nothing

this is very simple COM object. if i run the above script, it will show message box "10".
once i press ok, there is an popup with an exception message below.

---------------------------
WScript.exe - Application Error
---------------------------
The exception unknown software exception (0xc0020001) occurred in the application at location 0x7c812aeb.

Click on OK to terminate the program
---------------------------
OK
---------------------------

if i remove /clr switch and build it run the Vbscirpt. i don't see the popup error.

any suggestion why there an exception when /clr switch is used ?

Thanks in advance.

modified 23-Aug-17 6:26am.

GetUsbDrive letter error

Member 101933363-Aug-17 0:27

Member 10193336

3-Aug-17 0:27

I m using VC++ VS2008 compact edition. I hv problem that
when I m using

GetUsbDriveLetter(CString)

at compiled time error occurred not defined because it is in

Quote:
winbase.h

sdk function. And CE7 hv different sdk therefore it occurred. please suggest me how to get USB letter in CE7

YogeshJadhav

Re: GetUsbDrive letter error

Richard MacCutchan3-Aug-17 1:18

Richard MacCutchan

3-Aug-17 1:18

I cannot find that function in the latest version of winbase.h, and MSDN does not seem to have heard of it. What version of the SDK do you have that includes it?

Re: GetUsbDrive letter error

Member 101933363-Aug-17 2:26

Member 10193336

3-Aug-17 2:26

actual error is

Error	294	error C3861: 'GetLogicalDriveStrings': identifier not found

and using Toradex_CE700 platform using VC++

Microsoft Visual Studio 2008
Version 9.0.30729.1 SP
Microsoft .NET Framework
Version 3.5 SP1

Installed Edition: Professional

Microsoft Visual C++ 2008   91605-130-0752752-60490
Microsoft Visual C++ 2008

Crystal Reports    AAJ60-G0MSA4K-68000CF
Crystal Reports Basic for Visual Studio 2008


Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB2483802)   KB2483802
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/2483802.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB944899)   KB944899
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/944899.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB945282)   KB945282
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/945282.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB946040)   KB946040
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/946040.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB946308)   KB946308
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/946308.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB946344)   KB946344
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/946344.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB946581)   KB946581
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/946581.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB947171)   KB947171
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947171.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB947173)   KB947173
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947173.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB947180)   KB947180
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947180.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB947540)   KB947540
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947540.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB947789)   KB947789
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947789.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB948127)   KB948127
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/948127.

Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU (KB953256)   KB953256
This hotfix is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this hotfix will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/953256.

Microsoft Visual Studio 2008 Professional Edition - ENU Service Pack 1 (KB945140)   KB945140
This service pack is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this service pack will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/945140.

Microsoft Visual Studio 2008 Professional Edition - ENU Service Pack 1 (KB947888)   KB947888
This service pack is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this service pack will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/947888.

Update for Microsoft Visual Studio 2008 Professional Edition - ENU (KB956453)   KB956453
This update is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this update will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/956453.

Update for Microsoft Visual Studio 2008 Professional Edition - ENU (KB967143)   KB967143
This update is for Microsoft Visual Studio 2008 Professional Edition - ENU.
If you later install a more recent service pack, this update will be uninstalled automatically.
For more information, visit http://support.microsoft.com/kb/967143.

Re: GetUsbDrive letter error

Richard MacCutchan3-Aug-17 2:28

Richard MacCutchan

3-Aug-17 2:28

No mention of Windows CE in GetLogicalDriveStrings function (Windows)[^].

Re: GetUsbDrive letter error

Member 101933363-Aug-17 2:36

Member 10193336

3-Aug-17 2:36

yes, then any function to get usb drive letter in Windows CE 700 api

Re: GetUsbDrive letter error

Richard MacCutchan3-Aug-17 2:37

Richard MacCutchan

3-Aug-17 2:37

See my other reply below; it seems that Windows CE does not use drive letters.

Re: GetUsbDrive letter error

Richard MacCutchan3-Aug-17 2:32

Richard MacCutchan

3-Aug-17 2:32

See File Systems (Windows CE 5.0)[^]

Use ATL COM DLL in VB Script which written in C++

GTAVLover11-Jul-17 15:03

GTAVLover

11-Jul-17 15:03

Hello, I am newbie to C++ and therefore I found the following example and working with it.

A Beginner Tutorial for Writing Simple COM/ATL DLL For VS2012

I like to know how to use this example COM object in VB Script, I like to do it using CreateObject Method.

If it currently doesn't support VB Script, how can I add VB Script support to this DLL?

Thanks for your help. Thumbs Up | :thumbsup:

Re: Use ATL COM DLL in VB Script which written in C++

Richard MacCutchan11-Jul-17 21:35

Richard MacCutchan

11-Jul-17 21:35

See Using COM Objects in Windows Script Host (COM)[^].

Re: Use ATL COM DLL in VB Script which written in C++

GTAVLover11-Jul-17 22:02

GTAVLover

11-Jul-17 22:02

Thanks, I did it but I got "Could not locate automation class..." in VB Script, but using C# this works fine.

I used it like

Dim Test: Set Test = WScript.CreateObject("SimpleATLComLib.SimpleCom")

Test.TotalMarks = 50

because I don't know how to get automation class name to be used in VB Script from that DLL.

Why this error occurs?

Re: Use ATL COM DLL in VB Script which written in C++

Richard MacCutchan11-Jul-17 22:06

Richard MacCutchan

11-Jul-17 22:06

Sorry, no idea, I have not used VBScript in this way.

Get struct-members' names in Visual Studio console application?

arnold_w25-Mar-17 0:11

arnold_w

25-Mar-17 0:11

I need to debug an embedded C-application that contains a lot of the following structs:

MyStruct.MySubStruct.MyEnum

I have ported the code into a Visual Studio 2005 console application and I would like to dump all the struct-members (several hundred in total) to a text-file like this:

MyStruct.MySubStruct.MyEnum = MyEnumValue

I know this isn't possible in pure Visual Studio c programming language, but aren't you allowed to include C++ files as well in a Visual Studio console project? If so, is C++ capable of converting struct members and enums into text strings?

Re: Get struct-members' names in Visual Studio console application?

Richard MacCutchan25-Mar-17 0:35

Richard MacCutchan

25-Mar-17 0:35

arnold_w wrote:
pure Visual Studio c programming language

There is no such thing.

And your code above does not make clear what the problem is in sending the struct contents to a text file. Generally speaking you need to write the code to dump each element of the struct. Or you could just run the program in the Visual Studio debugger and examine the fields that way.

Re: Get struct-members' names in Visual Studio console application?

arnold_w25-Mar-17 0:58

arnold_w

25-Mar-17 0:58

Just like

__FILE__

generates a string with file name and

__LINE__

generates a string with the line number, I would like to have some way of generating strings with the structs' and members' names.

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