C++ - Load all filename + count the number of files in a current directory + filter file extension

Question

I want to count the number of file in the current directory as well as load all file names in the array. If possible, I want to know how to filter file extension also

Answer 1

The answer is Boost.Filesystem, specifically the directory_iterator.

Answer 2

Link the following program with -lboost_filesystem

#include <iostream>
#include <string>
#include <vector>

#include <boost/algorithm/string/case_conv.hpp>
#include <boost/filesystem.hpp>

int main( int argc, char ** argv )
{
  std::string ext = ".jpg";

  std::vector<std::string> files;

  for ( boost::filesystem::directory_iterator it( boost::filesystem::initial_path() );
        it != boost::filesystem::directory_iterator(); ++it )
  {
    if ( boost::filesystem::is_regular_file( it->status() ) &&
         boost::algorithm::to_lower_copy( it->path().extension() ) == ext )
    {
      files.push_back( it->path().filename() );
    }
  }

  std::cout << "Number of files: " << files.size() << std::endl;
  std::copy( files.begin(), files.end(), std::ostream_iterator<std::string>( std::cout, "\n" ) );

  return 0;
}