visual-c++

问题 I am using Windows 7 and I have to run one program in that windows but that program working in Windows XP. This is a Visual C++ program and I am using Visual Studio 2008 for this. When I am running my application, it does not throw any errors, but it does not create a directory in "c:\program files\". So can anyone help me to create directory and exe file? This is the code I am using: char szAppPath[MAX_PATH]; char szFileName[MAX_PATH]; DWORD dwResult; WIN32_FIND_DATA FindFileData; HANDLE

问题 #include <iostream> using namespace std; class Fraction { private: int num; int denom; public: Fraction() { int num = 0; int denom = 1; } Fraction(const Fraction& ref) { num = ref.num; denom = ref.denom; } Fraction(int arg) { num = arg; denom = 1; } Fraction(int arg, int arg2) { num = arg; if (arg2 == 0) denom = 1; else denom = arg2; } ~Fraction() { } void setnum(int arg) { num = arg; return; } void setdenom(int arg) { if(arg) { denom = arg; } else { denom = 1; } return; } int getnum() const

问题 #include <iostream> using namespace std; class Fraction { private: int num; int denom; public: Fraction() { int num = 0; int denom = 1; } Fraction(const Fraction& ref) { num = ref.num; denom = ref.denom; } Fraction(int arg) { num = arg; denom = 1; } Fraction(int arg, int arg2) { num = arg; if (arg2 == 0) denom = 1; else denom = arg2; } ~Fraction() { } void setnum(int arg) { num = arg; return; } void setdenom(int arg) { if(arg) { denom = arg; } else { denom = 1; } return; } int getnum() const

问题 I am trying to understand the visual cpp project document here (https://docs.microsoft.com/en-us/cpp/build/walkthrough-using-msbuild-to-create-a-visual-cpp-project). <Project DefaultTargets="Build" ToolsVersion="12.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"> <ItemGroup> <ProjectConfiguration Include="Debug|Win32"> <Configuration>Debug</Configuration> <Platform>Win32</Platform> </ProjectConfiguration> <ProjectConfiguration Include="Release|Win32"> <Configuration>Release<

问题 I am trying to understand the visual cpp project document here (https://docs.microsoft.com/en-us/cpp/build/walkthrough-using-msbuild-to-create-a-visual-cpp-project). <Project DefaultTargets="Build" ToolsVersion="12.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"> <ItemGroup> <ProjectConfiguration Include="Debug|Win32"> <Configuration>Debug</Configuration> <Platform>Win32</Platform> </ProjectConfiguration> <ProjectConfiguration Include="Release|Win32"> <Configuration>Release<

问题 Is there a "call stack" for compiler errors in Visual Studio 2005 (C++)? For example, I am using a boost::scoped_ptr as the value in a QHash. This is however causing the following compile error: 1>c:\qt\include\qtcore\../../src/corelib/tools/qhash.h(743) : error C2248: 'boost::scoped_ptr<T>::operator =' : cannot access private member declared in class 'boost::scoped_ptr<T>' From the build output I know which of my source files is causing the error and the line number in the qhash.h that is

问题 I have a CMake file which I'm using to build some CUDA on Windows (NVCC/MSVC). I'm trying to set the MSVC warning level to /W4 , using: add_compile_options("$<$<COMPILE_LANGUAGE:CUDA>:--compiler-options=/W4>") Building with CMake 3.9, I get this warning: (CudaBuildCore target) -> cl : Command line warning D9025: overriding '/W4' with '/W3' In CMake 3.15, the policy was changed to not automatically set /W3 in the CUDA flags, but with that version I get: (CudaBuildCore target) -> cl : Command

问题 I have a bunch of threaded tasks like this after each other: create_task(somewinrtasyncfunction()).then([this(variable_that_the_last_task_returned) { //task here return info; }).then([this](info) { //another task here return status}); Now I want to use status outside the tasks, in the function that called it. How would I access it? 回答1: You return the task (or value) created by create_task(...).then(...).then(...) . If you need to get the result synchronously, you can try calling .get() on

问题 I have a program which uses winapi functions. When it runs on WinXP (32bit) or Win7 (64bit) everything is OK. But on Win8 (64bit) there is a bug: sometimes program hangs on this code line HDC hDisplay = CreateDC("DISPLAY", NULL, NULL, NULL); What might be the reason of it? p.s. It is built in MSVC 2005 on WinXP 32 bit for platform Win32. 回答1: Try: CreateDC(TEXT("DISPLAY"),NULL,NULL,NULL) 回答2: I have managed to rebuild program for 64bit platform, and it works now. 回答3: While this question is

问题 In the code below I use mpf_add to add the string representation of two floating values. What I don't understand at this point is why 2.2 + 3.2 = 5.39999999999999999999999999999999999999 . I would have thought that gmp was smart enough to give 5.4 . What am I not comprehending about how gmp does floats? (BTW, when I first wrote this I wasn't sure how to insert a decimal point, thus the plus/minus digit stuff at the end) BSTR __stdcall FBIGSUM(BSTR p1, BSTR p2 ) { USES_CONVERSION; F(n1); F(n2)