How to count the number of files in a directory using standard?
I do not think that a way to easily get amount of files in directory exist, but you can simplify your code by using std::distance
instead of handwritten loop:
std::size_t number_of_files_in_directory(std::filesystem::path path)
{
using std::filesystem::directory_iterator;
return std::distance(directory_iterator(path), directory_iterator{});
}
You can get number of only actual files or apply any other filter by using count_if
instead:
std::size_t number_of_files_in_directory(std::filesystem::path path)
{
using std::filesystem::directory_iterator;
using fp = bool (*)( const std::filesystem::path&);
return std::count_if(directory_iterator(path), directory_iterator{}, (fp)std::filesystem::is_regular_file);
}
std::size_t number_of_files_in_directory(std::filesystem::path path)
{
return (std::size_t)std::distance(std::filesystem::directory_iterator{path}, std::filesystem::directory_iterator{});
}
There is no function to find out how many files are in a directory, only functions to iterate over it. The OS only has functions like readdir()
, ftw()
, FindFirstFileW()
so the standard cannot offer a better way.
(On the plus side that allows you to decide whether to, or how deep into, recurse into subdirectories)