How do you open a data file?

Answer 1

You can use fstream header file to read and write in files. It has two main components ifstream: stream which you can use to read data, and ofstream which allows you to save in files. Use something like this:

#include

#include

using std::ifstream;

using std::cout;

using std::endl;

int main()

{

char fileName[] = "myfile.txt";//file to read from

ifstream inData;//stream to read from myfile.txt

int data = 0;//to read one number of type int (we assume that the file contains it)

inData.open(fileName);//connect the stream to the file

if (inData.fail())//if coult not open the file, program will be closed

{

cout << "Could not open the file" << endl;

exit(1);

}

inData >> data;//read one number from the file and save it in data of type int

cout << "File contains a number: " << data << endl;//show data on the screen

inData.close();//close the stream connected to the file

system("PAUSE");

return 0;

}