I am trying to include a c# interface into a c++ header file which belongs to a clr library.
I add the additional directory and as soon as I include the interface and try to build the c++ project, I get loads of errors leading to the cs file, like:
Do I mess up some VS settings?
It is impossible to #include "IImagesToVideoConverter.cs". The C++ compiler cannot understand c# code. You need to put a c# project and a c++ project in the same solution, reference the c# project from the c++ project, and (i think) #using <the.dll>
including a C# source in a C++ compile makes no sense. They are different languages, why would you ever expect this to work?
Perhaps you want to make a COM interface between them, in which case you use a #import directive.
Related
How do you compile .cs files using C++
I have searched all through Mono's documentation and can't find a way to just compile C# code from the embedded mono runtime in C++. I know how to open a C# .exe assembly file using the embedded mono functions from C++, but I can't seem to find a way to just compile a .cs file to the .exe from C++.
I have also managed to compile the .cs files by calling the mcs.bat file from the CreateProcessA() function that Windows provides, however this does not give me a way to log errors or even check if it succeeded in compilation etc. (It also feels like a hack and not the official solution). The main reason I need to do this is so that I can recompile C# scripts on the fly by detecting when the source code has changed and another subset of conditions.
Does anyone know of a way to properly compile C# files using the embedded Mono runtime? And where to find the documentation for this? Currently I've been using the documentation here: http://docs.go-mono.com/?link=xhtml%3adeploy%2fmono-api-assembly.html which provides enough information for the most part.
Linking Mono in a DLL
Also, if you're familiar with embedding mono, do you know how to use it in a dll? I've managed to successfully link and compile it within a console application, but when I try to compile it as a part of a dynamic library, I get unresolved external symbol errors (specifically functions with the prefix __imp*).
Lastly, I'm using mono to embed C# as a scripting language for my game engine, however I don't know if there is a better (smaller) solution that I can use. If you know of any better solution feel free to leave a recommendation.
The mono runtime is a "Runtime", only for running the code,
but if you have installed the csc command then you can use this:
#include <cstdlib>
int main(){
system("csc yourfile.cs")
return 0;
}
I'm noob in C# and I already searched on the web. Anyway I'm still not sure about this and I do not have the total control of the code I have to implement, this is why I would like to be sure I needn't make any dll. I have a C++ file with a method, and I want to call this method from C# code. I just added "extern C" to the function.
When I just add the .h and .cpp files to the C# project they aren't detected. And of course, when I try to add it as reference, it doesn't work.
So do I absolutly have to make a dll ?
Your options for accessing the C++ code from C#:
Compile C++ as unmanaged DLL and access using p/invoke. This requires the C++ code be exposed using a C style API.
Compile C++ as unmanaged DLL and access using COM. This requires that you wrap your C++ in as COM objects.
Compile C++ as mixed/mode C++/CLI assembly and access the assembly as a managed reference. This requires that you wrap the original C++ as managed C++ ref classes.
All of these options, by necessity, involve the creation of another module/assembly. You cannot link the C++ code directly into your C# assembly.
You might like to try using the PInvoke Interop Assistant to generate the C# necessary to interact with the DLL via Platform Invoke. Be aware that this is imperfect though so YMMV.
Another alternative, if you have the knowledge and patience, is to make a COM component out of your native C++ DLL and consume that from C# by using the Type Library Importer to create a managed wrapper.
You won't be able to interact with .cpp/.h files since you need at least a binary object (assembly) for C# to interact with and C# won't generate any binaries from .cpp/.h. That's on the subject about adding these files as references to the project.
As for the argument that you don't have control over the code - well, don't make a DLL out of the actual .cpp/.h, but make your own thin DLL that has a wrapper object that just includes the headers, calls whatever method you would be calling and links to the appropriate .o files or .lib or whatever you have. If the interface changes you would just changed your thing wrapper which should be easy.
I have been looking for a way to call a function written in a C# EXE project (VS 2008) from a C++ DLL project. I can include the C# code as part of the C++ project itself if that is possible. All that I have been able to find is calling the C# DLL from C++.
Ultimately I want to call C# code from VB6 but I ask the question this way because I don't believe the later way is possible without an intermediate step.
Thanks,
Ian
Ultimately I want to call C# code from VB6 but I ask the question this way because I don't believe the later way is possible without an intermediate step.
You can register the C# classes to be visible to COM, and then call them directly from C++ or VB6.
For details, see the Example COM Class on MSDN, as well as Interoperability.
You can compile your c++ project with the /CLR option and then call C# from within it. To do that you need to include vcclr.h and then add a using statement for each dll you need to call from.
#include <vcclr.h>
#using <System.dll>
I have one C++/CLI project, a GUI application, which is compiled in mixed mode (managed+unmanaged).
Now I want to write a custom user control using C# and compile it to become CSharpA.dll.
my question is: Can this dll be used by my C++/CLI project easily? How would I do that?
Yes. Just add a reference to it. You may find yourself wanting using namespace directives, which, like the C# using directive, will add classes in other namespaces into the search space.
You only have to compile your C# code into an assembly, and this assembly can be referenced from your C++/CLI App as any other assembly.
I have a DLL that I've been using with no problem in Visual C# (simply adding the reference and using the namespace). Now I'm trying to learn C++, and I don't understand how you reference a namespace from a DLL. I can right-click on a project and select 'references' and from there click 'add new reference', but that just provides me with an empty 'projects' window. What am I missing?
C++ is a lot different from C#/VB.Net when it comes to processing DLL references. In C# all that is needed to do a reference is a DLL because it contains metadata describing the structures that lay inside. The compiler can read this information such that they can be used from another project.
C++ does not have the concept of metadata in the DLL in the sense that C# does. Instead you must explicitly provide the metadata in the form of a header file. These files are included in your C++ project and then the DLL is delay loaded at runtime. You don't actually "add a reference" so to speak in C++ but include a header file instead.
Once the header file is included, you can then access the namespace by including it in your CPP files
using namespace SomeNamespace;
First of all, if you are trying to use the same DLL you used in your C# application, if you are using pure native C++, it is not straightforward to make calls into that DLL. The problem is the DLL you are referencing in C# relies on the .NET framework in order to execute (it is a "Managed" DLL, as all C#, VB.NET and C++/CLI assemblies are). There is an easy way to reference "managed" code from C++ and that is by making a managed C++ project (AKA C++/CLI) (choosing from "CLR" section in the C++ project wizard in Visual Studio). Otherwise the only way to access the managed DLL is by exposing it to COM and using COM to access the object.
EDIT: The previous answer will be more helpful if you're using unmanaged c++; I assumed because of the C# reference that you were targeting managed C++.
The 'Add Reference' dialog should have a series of tabs - 'Projects' lists projects in the current solution; .NET lists the libraries installed in the GAC and 'Browse' lets you find a DLL yourself.
If you just want to add a reference to the DLL you should be able to do it with 'Browse'. If it's the output of a project you have the source to, add the project to the solution and it'll appear under the 'Projects' tab.
If this doesn't help, which version of Visual Studio are you using, and where/what is the DLL you want to use?