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I created a clr empty project and I added this code :

using namespace System;
using namespace System::IO;

int main()
	String^ fileName = "textfile.txt";

	StreamWriter^ sw = gcnew StreamWriter(fileName);
	sw->WriteLine("A text file is born!");
	sw->Write("You can use WriteLine");
	sw->WriteLine("...or just Write");
	sw->WriteLine("and do {0} output too.", "formatted");
	sw->WriteLine("You can also send non-text objects:");
	Console::WriteLine("a new file ('{0}') has been written", fileName);

	return 0;

now I want to add a library in c#, I added c# library and I add this to reference of c++ project and I addes this library to build dependencies but if I write in my source cpp:
#using "ClassLibrary1.dll"

there is an erroe: file not found.. and I added dll to c++ exe

What I have tried:

I tried what I wrote above..I tried to add a c# library
Updated 9-Mar-23 2:51am

Check the bin/debug folder and make sure that the DLL file is in there (or add a project reference instead of a file reference).
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Member 14594285 9-Mar-23 5:32am    
yes there is, there is an other error:
Severity Code Description Project File Line Suppression State
Error Unable to copy file "obj\Debug\ClassLibrary1.dll" to "bin\Debug\ClassLibrary1.dll".
OriginalGriff 9-Mar-23 6:05am    
That's probably why it doesn't work - if it can't copy the DLL to the executable folder, it won't be able to find it.
Try checking that no other processes / apps have the DLL open.
Member 14594285 9-Mar-23 6:11am    
I close all..error:
Severity Code Description Project File Line Suppression State
Error (active) cannot open metadata file "ClassLibrary1.dll" Project711 c:\Dev2015\Prg\Project711\Project711\Source.cpp 5

Severity Code Description Project File Line Suppression State
Error C1107 could not find assembly 'ClassLibrary1.dll': please specify the assembly search path using /AI or by setting the LIBPATH environment variable Project711 C:\Dev2015\Prg\Project711\Project711\Source.cpp 5

I added path of ClassLibrary.dll to command line but it's the same

This seems rather dated, but maybe it works for you:
Calling Managed .NET C# COM Objects from Unmanaged C++ Code[^]

But it should be simpler when using managed C++ (CLR project), see:
Interoperability with Other .NET Languages (C++/CLI) | Microsoft Learn[^]

It seems possible to use C# winforms from C++ too, see:
How to Integrate C# Window in C++ Project[^]

As I only have limited experience (only with calling C++ from C#), I can not be of much help in this matter.
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Member 14594285 9-Mar-23 8:57am    
with visual studio 2015 doesn't open
RickZeeland 9-Mar-23 9:00am    
Try the second example, its written for VS2015
Member 14594285 9-Mar-23 9:14am    
project works..a question..Can I use a dialog and not a console?
Member 14594285 9-Mar-23 9:42am    
it works..but a question..can I add a dialog?
RickZeeland 9-Mar-23 12:49pm    
See the updated solution above, good luck!

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