问题描述
我检查了有关c ++ 17下文件系统链接的很多问题,但仍然无法成功建立链接。我的 main.cpp
文件如下。
I have checked a lot of issues about the link of filesystem under c++17 and I still cannot make the link successfully. My main.cpp
file is as the following.
#include <experimental/filesystem>
int main(int argc, char** argv)
{
std::string imageDirectory = "./image";;
std::vector<std::string> imagePath;
for (const auto& entry: std::filesystem::directory_iterator(imageDirectory))
{
imagePath.push_back(entry.path());
std::cout << entry.path() << std::endl;
}
return 0;
}
我的 CMakeLists.txt
如下所示。
cmake_minimum_required(VERSION 3.8 FATAL_ERROR)
project(visual_hull LANGUAGES CXX)
set(CMAKE_CXX_STANDARD 17)
add_library(dataIO
STATIC
dataIO.hpp
dataIO.cpp)
find_package(OpenCV REQUIRED core highgui imgproc)
target_link_libraries(dataIO ${OpenCV_LIBS})
add_executable(visual_hull main.cpp)
target_link_libraries(visual_hull PUBLIC dataIO
stdc++fs)
错误如下。
/home/SENSETIME/zhangshunkang/Downloads/programming/c++/visual_hull/main.cpp: In function ‘int main(int, char**)’:
/home/SENSETIME/zhangshunkang/Downloads/programming/c++/visual_hull/main.cpp:15:31: error: ‘std::filesystem’ has not been declared
for (const auto& entry: std::filesystem::directory_iterator(imageDirectory))
^
CMakeFiles/visual_hull.dir/build.make:62: recipe for target 'CMakeFiles/visual_hull.dir/main.cpp.o' failed
make[2]: *** [CMakeFiles/visual_hull.dir/main.cpp.o] Error 1
CMakeFiles/Makefile2:72: recipe for target 'CMakeFiles/visual_hull.dir/all' failed
make[1]: *** [CMakeFiles/visual_hull.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2
推荐答案
您使用 std :: filesystem :: directory_iterator
。 std :: filesystem :: directory_iterator
和整个命名空间 std :: filesystem
在标头<$ c $中声明c>< filesystem> 。
You use std::filesystem::directory_iterator
. std::filesystem::directory_iterator
and the entire namespace std::filesystem
are declared in the header <filesystem>
.
您尚未包含标头< filesystem>
。相反,您包括了< experimental / filesystem>
。此标头未声明 std :: filesystem :: directory_iterator
。相反,它声明 std :: experimental :: filesystem :: directory_iterator
。
You haven't included the header <filesystem>
. Instead, you've included <experimental/filesystem>
. This header does not declare std::filesystem::directory_iterator
. Instead, it declares std::experimental::filesystem::directory_iterator
.
您可以始终使用任一标准文件系统库,或技术规范中的实验性文件系统库,但不得将它们混合在一起。如果您的目标是C ++ 17,则应使用< filesystem>
。
You can consistently use either the standard filesystem library, or the experimental filesystem library from the technical specification, but you must not mix them together. If you're targeting C++17, then you should use <filesystem>
.
理想的解决方案是将编译器升级到具有对C ++ 17的非实验支持的版本。否则,请使用实验性TS或Boost。
The ideal solution is to upgrade your compiler to a version that has non-experimental support for C++17. Otherwise use the experimental TS or Boost.
这篇关于在包含< experimental / filesystem>之后,尚未声明'std :: filesystem'。的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!