read from file only from one specific line to another C++

问题

Is there any way how to read data from file from line to another line ?

For example :

In file are these lines:

Line1: empty line

Line2: empty line

Line3: robert wa

Line4: frank le

Line5: silvia op

Line6: empty line

Line7: empty line

Line8: andy sf . .

And I need to only read everything from Line3 to Line6

So output will be : robert wa frank le silvia op

And my file have 300 lines that I want print.

Do you have any idea how to do it, or can you paste me some pseudocode

Thanks

回答1:

This should do the trick:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

    int main()
    {
        string line;
        ifstream infile;
        infile.open("putyourinputfilehere.txt");
        while(getline(infile, line))
        {
            if(line != "")
            {
                cout << line << endl;
            }

        }
        infile.close();
        return 0;
    }

回答2:

Use std::getline to read one line from an input stream (e.g. an ifstream). You can then print only those that you're interested.

回答3:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

 int main () {
  string line;
  ifstream myfile ("example.txt");
  if (myfile.is_open())
  {
    while ( getline (myfile,line) )
    {
      if(line.empty())
      {
        cout<<"Empty line";
      }
      else
      {
        //do some work
      }
    }
    myfile.close();
  }

  else cout << "Unable to open file"; 

  return 0;
}

来源：https://stackoverflow.com/questions/23209935/read-from-file-only-from-one-specific-line-to-another-c