I would like my C++/CLI headers to compile even when under another platform. Of course I am not expecting to compile them but just ignore them.
Would this be appropriate ? (_MSC_VER)
#ifdef _MSC_VER
using namespace System;
namespace ENMFP {
public ref struct Data {
};
}
#endif
Thanks !
You can use the __cplusplus_cli predefined macro documented here:
#ifdef __cplusplus_cli
using namespace System;
namespace ENMFP
{
public ref struct Data
{
// ...
};
}
#endif // __cplusplus_cli
Related
I hope I can explain myself.
Supose I have next:
File "A.h":
#include "C.h"
public class A{
// Some code...
}
File "B.h":
#include "A.h"
public class B{
A a = new A(); //With this line I mean I'm using one instance of "A" inside "B.h"
//Some code...
}
Is it possible to include "C.h" ONLY inside "A.h"?
My problem is that the code I've included is giving me a lot of conflicts with usual functions. It's not an option to correct conflicts one by one, because there is a huge set of them. Also, my "C.h" code included is only a test code: after some tests, I will delete the include line.
Is there any way of 'bubbling' my include?
Thank you in advance.
EDIT: A.h and B.h are on the same namespace.
Is it possible to include "C.h" ONLY inside "A.h"?
No. Not to my knowledge.
If you have name conflicts, just include C.h within an other namespace, as #user202729 proposed. This can help.
But I guess you use C in A for tests and you cannot use it in C in A without the implementation which is not compatible to C++Cli or content from B.h.
We used the pimpl ideom (pointer to implementation).
Example:
c++/clr currently does not allow do be included directly and that's why sometimes you cannot use libraries you want to use (like C.h), because they do rely on the support of .
This is my C.h ( used by all the other headers)
struct LockImpl; // forward declaration of C.
class C
{
public:
C();
virtual ~C();
public:
void Lock() const;
void Unlock() const;
LockImpl* _Lock;
};
This is my C.cpp (compiled without /clr )
#include <mutex>
struct LockImpl
{
std::mutex mutex;
};
C::C() : _Lock(new LockImpl()) {}
C::~C() { delete _Lock; }
void C::Lock() const
{
_Lock->mutex.lock();
}
void C::Unlock() const
{
_Lock->mutex.unlock();
}
A.h
#include "C.h"
public class A{
C c;
void someMethod()
{
c.Lock() // I used another template for a RAII pattern class.
c.Unlock()
}
}
I am developing a windows app in visual studio 2015 using C++. I need GetForegroundWindow() and GetWindowText() to return the app that is currently focusing on. However, it says GetForegroundWindow() and GetWindowText() are undefined even I've included "windows.h". I tried go to the definition of GetForegroundWindow(), it led me to "WinUser.h", so I included "WinUser.h" as well. But it still could not help. Here are my code:
#include "MainPage.xaml.h"
#include <windows.h>
#include <WinUser.h>
#include <winapifamily.h>
#include <string>
#include <stdio.h>
#include <iostream>
using namespace App1;
using namespace Platform;
using namespace Windows::Foundation;
using namespace Windows::Foundation::Collections;
using namespace Windows::UI::Xaml;
using namespace Windows::UI::Xaml::Controls;
using namespace Windows::UI::Xaml::Controls::Primitives;
using namespace Windows::UI::Xaml::Data;
using namespace Windows::UI::Xaml::Input;
using namespace Windows::UI::Xaml::Media;
using namespace Windows::UI::Xaml::Navigation;
using std::cout;
using std::endl;
MainPage::MainPage()
{
InitializeComponent();
}
HWND currenthwnd, hwnd = NULL;
char wnd_title[1024];
void App1::MainPage::Focus_app_Click(Platform::Object^ sender, Windows::UI::Xaml::RoutedEventArgs^ e)
{
currenthwnd = GetForegroundWindow();
GetWindowText(hwnd, wnd_title, sizeof(wnd_title));
cout << wnd_title << endl;
}
Any ideas? Thanks in advance!
GetForegroundWindowand GetWindowText in the WinUser.h are declared inside #if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) macro block. So you could use them only for windows desktop applications.
I would like to wrap a complex c++ class which used opencv object with c++/cli for using in c# and vb. I'm using Visual Studio 2015. I'm using the x64 versions of of the OpenCV library and compiling also to x64.
Following is the header.h file of a small test class, just as an example:
#pragma once
#include <vector>
#include "opencv2/opencv.hpp"
using namespace std;
class compC
{
public:
compC(int * pInt, int arrSize);
int sumArray();
private:
vector<int> vec;
cv::Mat img;
};
This is going to be compiled as a win32-application to a .lib file without any problems.
The example wrapper class (wrapper.h) would look like:
#pragma once
#include "../ConsoleApplication1/header.h"
#include "../ConsoleApplication1/body.cpp"
using namespace System;
namespace WrapperLibrary {
public ref class WrapperClass
{
public:
WrapperClass(int * pInt, int arraySize);
int getSum();
private:
compC * pcC;
int sum;
};
}
The second class would be compiled as a dll with /clr (as c++/cli project).
First I got an error that opencv.hpp could not be find and had to add the include directory of opencv in to the wrapper project. But I cannot compile it and get a lot of errors, mainly pointing to linking problems "unresolved external problems ..." in connection with the opencv-mat object.
If I remove the lines
#include "opencv2/opencv.hpp"
and
cv::Mat img;
in the test class (header.h) all will be fine.
What did I made wrong? How can I wrap those c++ class with c++/cli?
When creating a new class while working in a project that is based around windows application forms. I have a problem where string becomes unusable. I get errors the say things like
"a member of a managed class cannot be of a non-managed class type"
"IntelliSense: a function type involving a generic parameter cannot have an ellipsis parameter"
"IntelliSense: linkage specification is incompatible with previous "bsearch_s"(declared at line 426)"
Person.h
#pragma once
#include <string>
using namespace std;
ref class Person
{
public:
Person(void);
string name;
};
Person.cpp
#include "stdafx.h"
#include "Person.h"
#include <string>
using namespace std;
Person::Person(void)
{
name = "Bob";
}
If someone has a solution to this or a work around that isn't creating my own string class I would love to hear it as this has been bothering me for days.
String header in CLI C++ is already included in the System namespace.
String works as a pointer. Using the cap ^ handler
//This works:
#include "stdafx.h"
using namespace System;
void function()
{
String^ simpleStr = "Bob";
}
I am trying to replace Poco::AutoPtr with some alternative in boost. Here is what I have discovered so far:
What I have: below classess are being used with Poco::AutoPtr. They need to implement reference counted method with implementing duplicate() and release() methods.
I am using above referece_counted.h and Poco::AutoPtr in a complex class hierarchy with multiple inheritance and c++ diamond problems.
A simplified version of classes would look something like this
class A : virtual public ReferenceCounted
{
...
}
class B : public A
{
...
}
class C : public A
{
...
}
class D : public A, B
{
...
}
and the list goes on for few more level deep. I know that this needs to be refactored with a simplified hierarchy but I wanna remove Poco::AutoPtr first with proper replacement in boost:
What I have found so far:
I have found that boost::intrusive_ptr is the closest smart pointer that can be a good replacement of Poco::AutoPtr.
I am however not able to implement the proper solution with this because the intrusive_ptr requires intrusive_ptr_add_ref and intrusive_ptr_release methods created specifically for each class with which I need to use the pointer. I tried using templates but still not having proper solution at hand.
Also one more issue is that I need to typecast from base to derived class many times.
is intrusive_ptr is the correct smart pointer for this usage ? and if yes.. can anybody give me suggestion regarding how to use the same ?
I am however not able to implement the proper solution with this
because the intrusive_ptr requires intrusive_ptr_add_ref and
intrusive_ptr_release methods created specifically for each class with
which I need to use the pointer.
No-no. It is should not be hard. As Boost documentation says:
On compilers that support argument-dependent lookup,
intrusive_ptr_add_ref and intrusive_ptr_release should be defined in
the namespace that corresponds to their parameter; otherwise, the
definitions need to go in namespace boost.
Try this: main.cpp (built ok with "g++ main.cpp -o main -lboost_system")
#include <boost/intrusive_ptr.hpp>
class MyObject
{
public:
void duplicate(){
// ...
}
void release(){
// ...
}
};
namespace boost {
template <class T>
void intrusive_ptr_add_ref( T * po ) {
po->duplicate(); // your internal realization
}
template <class T>
void intrusive_ptr_release( T * po ) {
po->release();
}
}
int main(int argc, char **argv)
{
// ...
boost::intrusive_ptr<MyObject> ptr( new MyObject );
boost::intrusive_ptr<MyObject> ptr2 = ptr; // should work
}