User Program Communication
Read from Text File in C++
Used to read from a text file.
Syntax
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
//input stream
ifstream openFile(fileName);
if (openFile.is_open()){ //checking for existence of file
string stringToStore; //string to store file line
getLine(openFile, stringToStore); //gets a line from the file
openFile.close(); //closes file after done
}
Notes
Ifstream is the object created from the file, used for input.
getLine increments the file line automatically on every call.
Example
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
int main(){
//input stream
ifstream grades("names_grade.txt");
if (grades.is_open()){
string gradeAndName;
while(getLine(grades, gradeAndName){
cout << gradeAndName << \n;
}
grades.close();
}
}
