FileInOutExceptionDEMO.cpp

//************************************************************************
// Author: Rolando Carreon
// Date: apr 3 2025
// Language: C++
// Assignment: Demo
// Description: write to and read from a fule, using exception handling
//              to manage files not being opened
//************************************************************************

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

int main()
{
    // declare local variables
    string studentFirstName;
    string studentLastName;
    double studentGrade = 0.0;
    double totalGrades = 0.0;
    int countOfRecords = 0;
    
    // try to create the file
    // try to see if u have permissions to open and edit
    try
    {
        // create a ouput fule stream to file
        ofstream studentFile( "student.txt" );
        
        // add data to the file
        studentFile << "Sam Read 92.3\n";
        studentFile << "Fred Flinstone 89.2\n";
        studentFile << "Bart Simpson 72.5\n";
        studentFile << "Sally Smith 98.3";
        
        // close the file
        studentFile.close();
    }
    catch (...)
    {
        cout << "Yikes = something happened - the file was not writtin.\n";
    }
    
    
    // try to open the file and read the contents
    try
    {
        // crate a file input stream and read the data
        
        ifstream studentFile("student.txt");
        
        // read the data one line at a time
        //while ( studentFile )
        // use this while instead so it stops loop at the end of the file
        while ( !studentFile.eof() )
        {
            // read a line of data
            studentFile >> studentFirstName >> studentLastName
                        >> studentGrade;
            
            // display the student data
            cout << "Student: " << studentLastName << ", "
            << studentFirstName << "\tGrade: " << studentGrade << endl;
            
            // add studentGrade to the totalGrades, increment the count
            totalGrades += studentGrade;
            countOfRecords++;
            
        }
        
        // close the file
        studentFile.close();
        
        //calculate and display the average grade
        cout << "Average of Class is: "
             << totalGrades / countOfRecords << endl;
    }
    catch (...)
    {
        cout << "Yikes - something happened - the file was not opened.\n";
    }
    
    return 0;
}