I am trying to use the Console::SetCursorPosition(int, int) method. When I add the line using namespace System;, as shown in the C++ example from the preceding MSDN documentation, I get the error "Error: name must be a namespace name". I have been trying stuff for a couple hours now, but frustratingly without success. I have come across a ton of documentation for Visual Studio 2010 and 2012, but very little for 2013. The closest I have come is Lib Files as Linker Input. Steps 1-3 are easy enough, but step 4 is not clear to me: "Modify the Additional Dependencies property.". Looking at what is already there, it seems like I can just add a .lib file. But I don't have a System.lib.
So frustrated, so confused.
How can I use the System namespace in Visual Studio 2013 Update 4 for C++?
To formalize and expand on my comment, the Console class and generally the System namespace are part of the .NET framework.
In that context, the "C++" tab included in the MSDN documentation page of the Console::SetCursorPosition(int, int) method actually refers to the C++/CLI language. The C++/CLI language is distinct (although intentionally similar) from the C++ language. Correspondingly, the C++/CLI language contains various constructs which are not recognized by the C++ compiler toolset used when compiling Win32 projects.
In other words, to get rid of the "Error: name must be a namespace name" error, you would need to convert your Win32 C++ project to a CLR project. The easiest way to do that would be to create a new project, selecting one of the templates under "Visual C++" / "CLR":
The equivalent of .lib file depdendencies (relative to your Lib Files as Linker Input link) of Win32 projects for CLR project would be assembly references. You'd then typically add those assembly references with "Add References" under "Common Properties , References" project properties:
However, in your specific case you may very well find out that the System assembly reference is already included as part of the CLR project template.
You may want to check How to: Add or Remove References on MSDN for more details.
Finally, if you absolutely want to manually convert an existing Win32 project, you would need to set the "Common Language Runtime Support" project properties under "General" and the "C/C++ , General" tabs to one of /clr, /clr:pure, /clr:safe or /clr:oldSyntax (depending on your specific application requirements; if you're just toying around you might want to start with /clr) for all Configurations and Platforms as well as specify the targeted .Net framework version by directly editing the .vcxproj (as indicated in this answer). You would also still need to add assembly dependencies as with the new project approach above.
You have to set Common Language Runtime Support (/clr) in Configuration Properties - General:
And in Configuration Properties - C/C++ - General:
You are having a project of Win32 Console Application and and you are using .NET namespace. In Win32 Console Application only 4-5 namespace are there in standard library including std. Try using namespace std; at the top.
Related
I'm building an application using Qt 5.3.1 in Visual Studio 2012. I also want to use a hardware library which requires me to add a simple ATL object to the project. This can be done by using a Visual Studio wizard. The wizard complains that my project is neither an MFC executable nor an MFC DLL with full ATL support.
My question is: How can I add this support to my application? In the project properties I configured the project to link to the ATL and use the MFC. It did not work. Both statically and dynamically.
If there's another solution in order to add a simple ATL object to the project, please let me know.
The wizard which adds ATL support works on source code of the C++ project, including both checking if the current code is already ATL project, whether the project is okay for adding ATL support to, and code modification per se.
If the wizard "does not like" something in your project it displays an error which basically means that the wizard does know how to safely modify your source code. It does not however mean that adding ATL support is impossible. And enabling an option in project settings is insufficient since source code needs some explicit initialization stuff.
The best you can do to add ATL support without thinking too much about it, is to create a new empty project that matches the project type you currently have, e.g. MFC application. Then take a snapshot of source code, then add ATL support using the wizard. Then compare changes and duplicate them on your real project. The same applies to next step of adding ATL Simple Object using Visual Studio wizard.
Some relevant links (even though the method above looks the easiest to me):
How To Add ATL Support to an MFC EXE
Adding ATL support to existing mfc application
Add automation support to MFC DLL
I had a C++ project which was running perfectly. Now I copied the project to another folder and added the project to a WPF application solution.
Now the C++ project is giving me lot of build errors. One of them is "System' : a namespace with this name does not exist".
Below are the lines which creates this error.
#include "stdafx.h"
using namespace System;
using namespace System::Reflection;
using namespace System::Runtime::CompilerServices;
using namespace System::Runtime::InteropServices;
using namespace System::Security::Permissions;
The above lines are in AssemblyInfo.cpp file. I don't have any experience of C++, so finding it difficult to remove the errors. Any help is appreciated. Below is another error which might be helpful for you to resolve the issue.
managed targeted code requires a '/clr' option
Thanks in advance.
Set Common Language RunTime Support to be "Common Language RunTime Support (/clr)" in 2 places in your project properties :
For Visual Studio before 2019:
Configuration Properties -> General
Configuration Properties -> C/C++ -> General
For Visual Studio 2019:
Configuration Properties -> Advanced -> C++/CLI Properties
Configuration Properties -> C/C++ -> General
Mif's answer was a little incomplete for me. If you still have the issue, you'd might want to check if you set the correct C++-version.
For me it specifically needed ISO C++17 because the VS default preset ISO C++14 (at least a preset in my version) does not support the required CLI-packages. Thus, still set the Runtime support to Common Language RunTime Support (/clr) and set the correct C++ Language Standard in the Configuration Properties -> General tab.
Note: As of now (October 2021) ISO C++20 is currently not supported in CLI and will also fail to find System - I only found the 17-version to be compatible.
Since its a little easer the visual way, here the screenshots. And also don't forget Yinon_90's hint to have the version as well as dependencies installed!
It was not enough for me when I just changed "Common Language RunTime Support (/ clr)".
I had to create the project in VS which would be a dedicated project for CLR:
If you cannot see this option, you should add it in the VS installer first:
I came across the Framework and References tab of my project and noticed that I can "Add New Reference..." to my project, what is this functionality?
References are used to pull additional libraries into your project. For example, when you're creating a Windows project, you'll be using Windows forms, XML parsers, socket libraries, and lots of other useful stuff. Now, you could create all these from scratch, but that would be an insane undertaking. Instead, you can use libraries which have been pre-built, such as System.Windows.Forms (all the form stuff), System.Xml (XML parser stuff) and others.
Down at the low level, these are all DLL files precompiled by Microsoft and distributed along with Visual Studio. Add Reference allows you to add new ones of these to your project, for example, Managed DirectX for 3D isn't something which is commonly used, so must be manually added to a project.
I've also just noticed the C++ tag on this, so this may actually sound very patronising (as I may have gotten the scope of the question wrong), in which case, I didn't mean it. For C++, it will be used for C++/CLI, which is Microsoft's attempt to allow C++ to use the .NET framework.
For C/C++ in Visual Studio 2010 Express, adding a project reference (see first image, text in German, but you get the idea) adds a node as follows to the .vcxproj file:
<ItemGroup>
<ProjectReference Include="..\Ws1Lib\Ws1Lib.vcxproj">
<Project>{22c9de39-f327-408b-9918-187c0ee63a86}</Project>
</ProjectReference>
</ItemGroup>
This will make the static library produced by the referenced project available to the referencing project and also add a non-removable project dependency (right-click the project and select project dependencies, see second image) to the referencing project.
(The effect of such click actions on project configuration files become apparent when you put the project configuration files under version control and then look at the diff.)
To create setup where one or more projects reference a static library project, see this MSDN guide:
Walkthrough: Creating and Using a Static Library (C++)
I'm normally working in c# so certain things in c++ keep confusing me alot (they seem so diffrent yet the names almost the same)
I created a Console project in which i want to run a diffrent project for testing purposes. i added the project as a reference to the console app, and then got kinda stuck.
there is no namespace in the projects, so i can't do a using and if i try to include the other file, it cannot find it (and i want to avoid being unable to debug through it all).
the code for the class can be found here(ignore the c# part), the console is just a standard console with nothing in it yet.
Yeah, C++ doesn't have the notion of assemblies that exists in C# and .NET. It makes tasks like this slightly more difficult, a virtue of the fact that C++ compiles directly to native code.
Instead, you'll generally #include the necessary header files (*.h) at the top of your code file, and instruct the linker to link to the appropriate .lib file(s). Do that by going to your project's Properties, selecting Linker -> Input, and adding the file to the "Additional Dependencies" section.
As an alternative to linking to the .lib file, you can use Visual Studio to add a reference to the other project, if it's part of the same solution. Microsoft has a walk-through on creating and using a dynamic link library in C++ that might be worth a read.
I'll assume you're using Visual Studios:-). You have to tell
the compiler where to look for its includes. Under Visual
Studios, open the properties page for the project, then go to
Configuration Properties->C/C++->General, and add the necessary
directories in the entry Additional Include Directories. (If
the other project is in the same solution, use a relative path.
But I think the dialog box that pops up when you click on the
button on the right does this automatically. I'm not a great
fan of all this GUI stuff in general, but Microsoft seems to
have done this particular part quite well.)
Once you've done this, you might have to go through a similar
process for linking: this time it's under Configuration
Properties->Linker->General, and the entry is called Additional
Library Directories, but the principle is the same. (This may
not be necessary, if you're putting all of the dll's and
executables in the project in the same directory.)
I am developing a C++ library that I want to pass on to my team. The library has just one class with a bunch of methods.
So, I have developed the class definition file (X.cpp) and a corresponding class declaration file (X.h).
Here are my questions --
In Visual Studio 2005, whats is the most straight forward way to build this library as a DLL, such that I get the following files:
X.lib : which I can pass to my team so they can link against my library
X.dll : which I can pass to my team for run-time
Instead of a DLL, should I rather be going the static library way ?? If so, how do I go about doing this in Visual Studio 2005 & will this give me a X.lib file that I can pass on to my team ?
Any explanations or references are very welcome.
Thank you very much.
The easiest way to build a DLL, is New->Project->Win32 Console Application. Then on the dialog select DLL and select "Exports Symbols". This will synthesize a dll with a .h, and .cpp file which demonstrate how to export your classes. You can get rid of this .h/.cpp but first import your class add the appropriate #ifndef statements. Now as far as DLL versus Static library if its a single small class, that doesn't change particularly often you might be better off with a static library, its simple, its concise, it doesn't add another dependency which needs to be shipped with your product. A DLL is nice if the code in the .cpp file changes often (ie. the function implementations) because you can just swap in the new DLL.
From your description, it looks like you already have a Visual C++ project (correct me if I'm wrong). If so, when you go into project properties, under "General" you can find "Configuration Type" - switch it to "Static library" or "Dynamic library" as needed.
If you choose "Static library", then you will just get a .lib file that can be immediately used.
If you choose "Dynamic library", and you export any functions from your DLL (e.g. by marking them with __declspec(dllexport)), an export .lib will be generated automatically.
It's hard to tell which option is preferable without knowing the specifics of what you're doing. In general, I'd recommend defaulting to static libraries, because it's usually good enough, and there are more traps when dealing with DLLs (especially ones that export C++ symbols).
I think that, in most cases, a dll is a better choice than a static lib because your team will not have to recompile their code when you distribute a new version of your library.
I struggle with this too sometimes.. because I can't find where the elusive setting is within C++ Project Properties.. So I decided to jot it down for my own sanity as a blog post.
HTH