I've scoured the web and stackoverflow for this answer but can't find anything. I have written a com object in C++ (for the fist time) that works when used in vbscript and through cocreateinstance in an executable file. So I decided to see if it would work in Excel VBA.
So I went into "References" and located my object there. Checked the box and started coding away. The following is the VBA code.
Function doCos(x As Double) As Double
Dim t As SimpleLib.IMath
Set t = New SimpleLib.IMath ' <- "Invalid use of New keyword" error here
doCos = t.Cos(x)
End Function
Intellisense recognizes my object in the Dim statement, but it does not appear when I use a Set statement. Obviously I am using a registered type library or else intellisense wouldn't work at all. Again, the com object can be used in vbscript or an executable, but for some reason can't be used, at least with the new keyword, in VBA.
Does anyone have an idea what may be wrong, or what may have to be added to the com object? Thanks.
One approach is to define a coclass in the IDL that includes the interface needed (IMath in my case). NOTE: That the [default] interface is hidden by default. So I simply defined interface IUnknown as the default. After compiling with MIDL a type library is generated which one should register with regtlibv12.exe.
I then included an additional IF statement in DllGetClassObject like if (rclsid == CLSID_Math) where CLSID_Math is corresponds to the CLSID defined in the file automatically generated from MIDL. All I did was copy and paste the body of the IF statement from if ( rclsid == IID_IMath ), updated the DLLRegisterServer and DLLUnRegisterServer functions, recompiled the project, and regsvr32.exe.
So the following works now.
Function docos(x As Double) As Double
Dim a As SimpleLib.IMath
Set a = New SimpleLib.Math
docos = a.Cos(x)
End Function
Thanks to Hans for the tip about the coclass. Learned something new and useful.
Related
First of all happy new year to everyone, hope you're doing well!
I'm working on a C++ project in which I need to call a C# DLL I created following the first answer of this post. Once I have the DLL, I need to call it from Qt, so by using dumpcpp and the .tlb file generated by regasm, I managed to get the .cpp and .h files to use my classes. Just as a reference, the namespace of the classes is Wrapper, and the main class is Device with guid {DD4A4896-C105-4C60-839B-B18C99C8FE15}.
Once I have the generated files to use the DLL, if I try to create a Wrapper:: Device instance on Qt, I get the following error:
QAxBase::setControl: requested control {dd4a4896-c105-4c60-839b-b18c99c8fe15} could not be instantiated
QAxBase::qt_metacall: Object is not initialized, or initialization failed
It doesn't give any more information, so I tried to check if the guid was stored on the system registry (I used the regasm command explained on the previously quoted post, and It said that it was successful, but you never know). Opening Registry editor and searching for the Guid revealed that it's present at: Computer\HKEY_CLASSES_ROOT\WOW6432Node\CLSID\{DD4A4896-C105-4C60-839B-B18C99C8FE15}, which, as far as I know, is the right route for these guids, and it points to the right DLL.
I though It may be due to some kind ActiveQt problem, and as the previously quoted post explained how to use that DLL from VS C++, I decided to give it a try, using this as an another reference. I've finished with this code, which is supposed to create an instance of my Device object
#include <iostream>
#include <atlstr.h>
#import "C:\Users\javie\Documents\Wrapper\Wrapper\bin\x86\Release\netstandard2.0\Wrapper.tlb" named_guids raw_interfaces_only
inline void TESTHR(HRESULT x) { if FAILED(x) _com_issue_error(x); };
int main()
{
try
{
TESTHR(CoInitialize(0));
Wrapper::IDevicePtr devPtr = nullptr;
TESTHR(devPtr.CreateInstance("{DD4A4896-C105-4c60-839B-B18C99C8FE15}"));
}
catch (const _com_error& e)
{
CStringW out;
out.Format(L"Exception occurred. HR = %lx, error = %s", e.Error(), e.ErrorMessage());
MessageBoxW(NULL, out, L"Error", MB_OK);
}
CoUninitialize();// Uninitialize COM
std::cout << "Hello World!\n";
}
However, this doesn't work either, the createInstance method throws an exception of Class not registered and HR=80040154. Again, according to Registry editor, the class is registered, so I don't understand the error. I've also tried with devPtr.CreateInstance("Wrapper.Device"), devPtr.CreateInstance("Wrapper::Device") or `devPtr.CreateInstance("Wrapper::CLSID_Device") as the links I posted suggest, but in those cases I get another exception with HR=800401f3 and message Invalid class string.
It doesn't matter whether VS or Qt Creator are opened as administrator or not, I get the exact same error.
I have run out of ideas, and I really need to be able to use that DLL from Qt using the files generated by dumpcpp.
Does any one know what could be happening? It feels quite strange to me.
If your C++ application is 64-bit, that's the answer right there, because your C# component is 32-bit (or MSIL but registered to the 32-bit hive). In situations like these, a simple test using VBScript is always useful.
Write a simple VB Script (test.vbs)
Dim obj
Set obj = CreateObject("Wrapper.Device") ' or whatever your ProgID is
MsgBox TypeName(obj)
Now, run this macro 2 ways: with 32-bit and 64-bit versions of VBScript:
32-bit > c:\windows\SysWow64\cscript.exe test.vbs
64-bit > c:\windows\system32\cscript.exe test.vbs
This is assuming your C# component is dispatch compatible. If it's not, then it will still give you differing results that you can use to debug.
Assuming automation/IDispatch compatible, one will work and one won't if you have registered your component correctly.
Have you registered correctly? When I use regasm, I always use the the switches /tlb /codebase when registering the C# component for COM.
Ok, in case someone find the same error, I'll explain the solution I found.
The problem was that in my case, the C# class I developed depended on another 32 bits dll which was not registered on my PC. Once I registered the other dll, everything worked fine.
I don't know why VS kept telling me that the class was not registered when my class itselft was registered, it was one of its dependencies that wasn't registered.
Anyway, I discovered this thanks to Joseph's comments, so thanks a lot for your help.
I got a c++ demo that has successfully called the API written in c++, now am trying to call those API from excel VBA. I've done quite a bit research but still not able to link them together.
Basically there's a API(TapQuoteAPI.dll) export function like this in demo
'TapQuote.h
TAP_DLLEXPORT const TAPICHAR *TAP_CDECL GetTapQuoteAPIVersion();
in demo c++ solution(TapQuoteAPI_Demo), i include the 'TapQuote.h' in demo.cpp,
the cout<<GetTapQuoteAPIVersion()<<endl; is successfully called, and result is print.
but when it comes to call this function in excel vba, i keep failing.
I tried to directly use the TapQuoteAPI.dll in excel like this, but not working.
Declare Function GetTapQuoteAPIVersion Lib "D:\Proejct\WIN32\TapQuoteAPI.dll" () As String
Then I also try to build another dll function with a deFile.def from TapQuoteAPI_Demo.dll since i successfully call it within the c++ demo.
Declare Function GetTapQuoteAPIVersion Lib "D:\Proejct\WIN32\TapQuoteAPI_demo.dll" () As String
also failed.
Could anyone shed some lights for me please?
I have written a DLL function in C++, which I am calling from VBA (Excel).
How can I setup the Visual Studio properties to allow me to debug the function? I have tried specifying Excel, but that doesn’t seem to work.
You have two choices: "direct debug", or "attach".
I strongly prefer the "direct debug" approach for a long list of reasons omitted from here.
There are steps required on both the DLL and Excel/VBA sides, your posting is unclear if all of those steps are addressed.
There are variations on the following:
1) In VS, depending on the version, enter Project Settings, or Project Properties, or equivalent, in the "Debug (not release) Target", go to the Debug or Debugging settings. :
a) There will be an field called "Executable for debugging session", or "command", or something like that depending on VS ver. Here, enter the full path of your Excel exe
b) Optionally, if the same "test spread sheet" is used frequently, enter the full path of your xls (or whatever) in the field called "Command argument", or "program argument" or as in your VS ver.
You may need to surround this with double quotes (e.g. if there are spaces in your path/file names).
c) You can also set the output of your project to a Dir that is "addin helpful", such as a Dir called AddIn (c.f. having the DLL end up in Debug (or Release) Dirs)
... it is assumed that your DLL has all the bits required to export the functions, with the project being of type DLL, plus any DLLEXPORT and compiler directives, etc etc.
... the specifics of the DLLEXPORT settings (and related compiler switches) and Calling Convention will determine many things ... it is assumed you have done all that correctly and consistently (and especially consistently with what the Excel-side is expecting).
... your DLL may or may not have a DLL_Main, if it does, more discussion is required.
2) Before anything else, be sure to have created the Excel-side "interface" for your DLL, ie. the "Add-In". This can be either via .xla, or via .xll. I strongly suggest the .xla route as your first approach.
See the Excel help files etc for creating the .xla
Then, in your XLA's VBA Module(s), declare the functions/subs etc from your DLL. For example, if you have a DLL called Add2_DLL.dll, which contains an exported function "add2_pho_xl", then:
Public Declare Function Add2_Pho_XX Lib "E:\EclipseWorkSpace\Add2_DLL\Debug\Add2_DLL.dll" _
Alias "add2_pho_xl" (A As Double, B As Double) As Double
I have used the Alias approach here, for reasons required below.
In many instances, this declaration can be used directly as User Defined Function (UDF) in your sheets, etc. However, for a vast number of cases, you will need to create a VBA "spinner" function/sub that creates the "ultimate" UDF, and relies on this direct entry function (see below). This is also a very long story, but necessary where more complex matters are required (arrays, variants, etc etc).
NOTICE:
a) the DLL's full path is required unless special steps have been taken. If your Addin is for general distribution ... a much longer discussion is required.
b) the Alias must be the EXACT entry name of the function in your DLL. If you view near the end of the DLL (or .Def) files, and unless you set your DLL modules as Private, those will show the entry names expected on the DLL side.
In this example, the entry name is NOT "decorated" due to the choices in the Calling Convention and compiler switches, but it could look something like
"_add2_pho_xl_#08" etc depending your choices.
... in any case, you must use whatever the DLL has.
3) Once both the .xla and dll exist (it is best if they are in the same Dir), Excel must be "told" about the Add-In. The easiest approach is Excel/Tools/Addins, but there are various strategies for "registering" DLL functions.
4) CRUCIALLY, the argument list properties/declarations MUST BE CONGRUENT with BOTH those in your DLL and the Calling Convention. Three (of many possible) examples of "issues" are,
(i) A Boolean on the VBA-side is two-bytes, if the Bool/Logical on your DLL side is 1-byte, then the Debug will fail, since the two sides "cannot connect" properly.
(ii) Strings ... this can be a very long story. It depends if sent ByVal or ByRef, it depends if the DLL side has "hidden length" Args, etc. etc. Remember, VBA uses COM/OLE VBStrings, which have their own can of worms.
(iii) Variants/Objects: these require a tome onto themselves
5) If ALL (and likely more) of the above have gone well, then in VS set your break points, if required, and "Go" or "Start" the debug (depending on VS ver, etc.). This should launch Excel, and if you also set the target xls, it will launch too. Go to the cell(s) where you addin function (e.g. =add2_pho_XX(A1, B1) ) resides, and execute the cell (sometimes using the "fx" menu item is useful, but there are other ways also).
Some hints:
a) if the func execution crashes/hangs etc Excel and does not even arrive back to the VS side, then likely there is a Arg list conflict (e.g. you are passing a Double to an Int or a million other possibilities), or Calling Convention conflict, etc.
b) In general, you may (while in the VS debug session) simultaneously perform a VBA debug session. That is, after starting the VS bebug, entre the VBA IDE, and set break points in VBA UDF's, if a "spinner" UDF's have been created. For example, a VBA UDF that relies also on the DLL's function.
Private Function Add2_Pho( FirstNum as Double, SecondNum as Double, Optional lMakeRed as Variant) As Variant
'
'
Add2_Pho = Add2_Pho_XX( FirstNum, SecondNum ) ' this is the actual DLL func accessed via Delcare above
'
If( IsMissing(lMakeRed) ) Then
Else
If( cBool(lMakeRed) ) Then
If( Add2_Pho < 0 ) Then
'
' ' make the result Red, or something
'
End If
End If
End If
'
'
End Function
... here, setting a break point at the first line can be helpful to see if the UDF is even entered on the VBA side. If it is, click Continue in VBA, and see if it makes it to the VS side, if not, check Args, Calling Convention, etc again, etc etc
c) If the cell's content are #Value or some other unexpected result, then at least the UDF is "recognised" but not functioning correctly, either due to sheet->VBA issues, or VBA-> DLL issues, or after the return DLL-> VBA
d) Save often! and Use the VBA IDE's Debug/ Compile VBA Project before running anything just make sure VBA internal consistency.
e) Also, if you are using VBA/XLA's, then get a copy of CleanProject (VBA can mess up its internals sometimes, and this Tool will be a life saver)
Please make sure that Debug mode is the active mode.
How to debug your DLL with Excel/VBA
I have recently modified one of my components, and it so happens it is no longer using one of the properties it used before.
However, those properties are written in multiple .dfm files throughout the project.
Now, when i try to compile the project, i get
"Error reading .: Property <...> does not exist"
The complicated part is that the property value is binary data (stored in multiple lines), and i cant just delete it with Delphi replace or notepad++ regexp (since they are single-line based).
So my question would be:
Are there any third party tools or ways to easily remove properties from multiple .dfm files?
Try this tool Delphi DFM properties remover, works with old versions of delphi but maybe can help you.
One possible approach is to modify your component so that it is capable of simply ignoring these properties. That way you don't have to hunt them down in each and every .dfm file.
For example:
type
TIgnoreFormPropertyHelper = class
public
class procedure IgnoreBooleanProperty(Reader: TReader);
class procedure IgnoreIntegerProperty(Reader: TReader);
end;
{ TIgnoreFormPropertyHelper }
class procedure TIgnoreFormPropertyHelper.IgnoreBooleanProperty(Reader: TReader);
begin
Reader.ReadBoolean;
end;
class procedure TIgnoreFormPropertyHelper.IgnoreIntegerProperty(Reader: TReader);
begin
Reader.ReadInteger;
end;
type
TMyComponent = class(...)
....
protected
procedure DefineProperties(Filer: TFiler); override;
....
procedure TMyComponent.DefineProperties(Filer: TFiler);
begin
inherited;
Filer.DefineProperty('MyLegacyBooleanProperty',
TIgnoreFormPropertyHelper.IgnoreBooleanProperty, nil, False);
Filer.DefineProperty('MyLegacyIntegerProperty',
TIgnoreFormPropertyHelper.IgnoreIntegerProperty, nil, False);
end;
The Jedi VCL contains a tool called DFMCleaner:
DFMCleaner is a tool to remove unsupported properties from DFMs. If
you save a dfm file in one version of Delphi and want to use it in an
earlier version, chances are there are some unsupported properties in
it, generating an error when the form is opened in Delphi. What's even
worse, if the dfm is part of a design-time package, Delphi will
install the package without errors but when you try to access the form
at design-time (f ex if the form is used by a property editor), Delphi
generates an AV instead.
It is located in jvcl-install\devtools\DFMCleaner (project with source code and example configuration file)
In my case simply closing the project and deleting the DProj file helped.
I have a need to create a Tcl extension that calls a managed .NET DLL/Class Library. Currently, the structure of my application is Tcl > DLL Wrapper (C++ CLR) > .NET Class Library (VB.NET), where ">" represents a function call.
My VB.NET DLL just takes a value and returns it back, keeping it simple for now. In the end, this will do some more advanced stuff that makes use of some .NET functionality.
Public Class TestClass
Public Function TestFunction(ByVal param As Integer) As Integer
Return param
End Function
End Class
My Tcl Extension (C++ CLR) creates an object of the type above
int TestCmd(ClientData data, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[])
{
// Check the number of arguments
if (objc != 2) {
Tcl_WrongNumArgs(interp, 0, objv, "arg");
return TCL_ERROR;
}
int param, result;
if (Tcl_GetIntFromObj(interp, objv[1], ¶m) != TCL_OK)
return TCL_ERROR;
SimpleLibrary::TestClass^ myclass = gcnew SimpleLibrary::TestClass(); //System.IO.FileNotFoundException
result = myclass->TestFunction(param);
Tcl_SetObjResult(interp, Tcl_NewIntObj(result));
return TCL_OK;
}
And finally, my Tcl script loads the extension and calls the function.
load SimpleTclExtension.dll
TestCmd 2
If my VB.NET DLL is in the same directory as my extension DLL, the extension crashes when it instantiates a TestClass object. I've noticed if the VB.NET DLL is relocated to C:\Tcl\bin, the extension will find it, and TestCmd can be called just fine. The problem is that this will eventually need to be deployed across a number of PCs, and it's preferred not to mingle my application's files with another application's.
It seems like there should be some configuration settings that will fix this problem, but I'm not sure where. Any help is greatly appreciated.
Firstly, depending on just what kind of Tcl application you are using you may want to look at Eagle which is a implementation of Tcl in CLR.
I think you are bumping into .Net's desire to only load assemblies from your application's directory or its immediate subdirectories. The application here is the tclsh/wish executable which is why moving the .Net assembly makes it load. This is something you can fix with suitable manifests or calls to the API to permit assembly loading from alternate locations. In this case I think you will need to run some initialization code in your Tcl extension when it gets loaded into the Tcl interpreter to init the CLR and add the extensions location as a suitable place to load assemblies from. It has been a while since I was looking at this so I forgot the details but I think you want to look at the AppDomain object and check the assembly loading path properties associated with that or its child objects. Try AppDomain.RelativeSearchPath
To be more specific, Eagle includes Garuda which is a Tcl extension built specifically to allow calling .Net from Tcl