c++ files
// basic file operations #include <iostream> #include <fstream> using namespace std; int main () { ofstream myfile; myfile.open ("example.txt"); myfile << "Writing this to a file.\n"; myfile.close(); return 0; }
c++ how to read from a file
#include <fstream> #include <iostream> using namespace std; int main() { /* You create a stream using the file in a * similar way to how we use other streams. */ ifstream in; // Open the file in.open("names.txt"); if(in.fail()) cout << "File didn't open"<<endl; int count = 0; string line; while (true) { /* Get line will work as long as there is * a line left. Once there are no lines * remaining it will fail. */ getline(in, line); if (in.fail()) break; /* Process the line here. In this case you are * just counting the lines. */ count ++; } cout << "This file has " << count << " lines." << endl; return 0; }
cpp read from file
freopen("filename.extension", "r", stdin);