use a COM ( or a .Net ) object in a c++ QT application

[franco.amato]

Hi to all I have a problem.
I have to build a program in C++ with Qt and I have to use some routines contained in a dll.
I have to version of the same dll

• com version
• .net version

I would know how to use the routines in my qt application. I read about ActiveQt but I'm not sure is what I need.
And which version of the dll can I use? The COM or the .net version?

Regards

[arpspatel]

you can use both .net and com version.. I dont know much about this, you can try looking into the examples provided in the Qt Installation. There are many examples, one such for COM version and also for .NET. They can provide more information about this.. try Qt Assistant which comes with Qt SDK, it has detail explanation of the coding for the examples and maybe on how to do what you are asking for...

[franco.amato]

you can use both .net and com version.. I dont know much about this, you can try looking into the examples provided in the Qt Installation. There are many examples, one such for COM version and also for .NET. They can provide more information about this.. try Qt Assistant which comes with Qt SDK, it has detail explanation of the coding for the examples and maybe on how to do what you are asking for...

I read the assistant and I gave a look at the example but I can not find for example the point where it load the dll

[arpspatel]

for loading dll u can use this.. its used in .NET activeQt example

#using <dllname.dll>

http://doc.qt.nokia.com/4.6/activeqt-dotnet.html

here is sample code from the example

#include <QString>
 
 #using <mscorlib.dll>
 #include <vcclr.h>
 
 using namespace System;
 
 String *QStringToString(const QString &qstring)
 {
     return new String((const wchar_t *)qstring.utf16());
 }
 
 QString StringToQString(String *string)
 {
     const wchar_t __pin *chars = PtrToStringChars(string);
     return QString::fromWCharArray(chars);
 }

#include <QString>

 #using <mscorlib.dll>
 #include <vcclr.h>

 using namespace System;

 String *QStringToString(const QString &qstring)
 {
     return new String((const wchar_t *)qstring.utf16());
 }

 QString StringToQString(String *string)
 {
     const wchar_t __pin *chars = PtrToStringChars(string);
     return QString::fromWCharArray(chars);
 }

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use can also use QLibrary for loading dlls, not sure if it will work for .NET or COM.. give it a try..

[franco.amato]

My problem is the inverse.
I would use a COM object in a C++ program

[franco.amato]

for loading dll u can use this.. its used in .NET activeQt example

#using <dllname.dll>

http://doc.qt.nokia.com/4.6/activeqt-dotnet.html

here is sample code from the example

#include <QString>
 
 #using <mscorlib.dll>
 #include <vcclr.h>
 
 using namespace System;
 
 String *QStringToString(const QString &qstring)
 {
     return new String((const wchar_t *)qstring.utf16());
 }
 
 QString StringToQString(String *string)
 {
     const wchar_t __pin *chars = PtrToStringChars(string);
     return QString::fromWCharArray(chars);
 }

#include <QString>

 #using <mscorlib.dll>
 #include <vcclr.h>

 using namespace System;

 String *QStringToString(const QString &qstring)
 {
     return new String((const wchar_t *)qstring.utf16());
 }

 QString StringToQString(String *string)
 {
     const wchar_t __pin *chars = PtrToStringChars(string);
     return QString::fromWCharArray(chars);
 }

To copy to clipboard, switch view to plain text mode 

use can also use QLibrary for loading dlls, not sure if it will work for .NET or COM.. give it a try..

Hi I'm trying your suggestion but I still don't understand how to get the pointer of the dll routines and call them.
Why there is no a simple and clear example?

as this:

code for load com/.net dll

code for load com/.net dll

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get routine pointers

get routine pointers

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call routine myroutine(param1, param2) with param 1 and 2

call routine myroutine(param1, param2) with param 1 and 2

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Is too difficult to provide a simple example?

[vxmontes]

Hi,

I have the same problem, looking for a simple example

Vitor