multiple reading from folder

[Updated version of my last post] I have situation where i have to read all the files from the directory and to get their size. I have some approach in my mind.I only interested in file name and size of the each individual file. What would be the best approach to get these two values.Thank you

#include <iostream>
#include <boost/filesystem.hpp>
#include <boost/range/iterator_range.hpp>
#include <fstream>
#include <string>
int main(){

std::string SourceFolder="C:\\testFolder\\";
boost::system::error_code ec;
path mDirectory(SourceFolder);

std::cout<<"Directory includes the following files"

if(is_directory(mDirectory)){
for(auto testFile=mDirectory.begin();testFile!=mDirectory.end();testFile++){
    std::cout<< testFile->string()<<std::endl;  // output?    
    std::cout<< testFile<<std::endl;           // output ?
    std::cout<< testFile->size()<<std::endl;  // output ?
    std::cout<<file_size(mDirectory,ec);     //output  ?

}

  return 0;
  }