Write Array of a Class to a file -- Overloading << Overloading

[iAqMGNh0]

Hey folks.
I am 96% finished with a final project for my first c++ course and I've run into trouble with writing out the array of my class to a file. I have read IN information to the class array from a .txt file just fine. But when applying the same logic to printing the same array out to a file I receive the following error message.

error: no match for 'operator<<' (operand types are 'std::ofstream {aka std::basic_ofstream<char>}' and 'void')

I've been looking into possible solutions. I know I should probably be overloading the << operator but I don't know exactly how to to that. I've looked at so many examples online but I can't seem to apply what I've been reading to my own code. Most people have told me to use vectors. I... do not know what a vector is. We haven't gotten that far in the course.

I've trimmed as much of the code as I can to the bare minimum but if any more code is needed I'll gladly share -- I just don't want to put too much of this assignment out there. It's a program the uses a switch-case menu to read in information and calculate a payroll (among other things).

class Employee
{
private:
    int empID;
    string empName;
    int day1, day2, day3, day4, day5;
    float empWage;
    float deduction;
public:
    void setData(int,string,int,int,int,int,int,float,float);
    void getData(void);
    void printMenu();
    void printEmpData();
    void printPayroll();
};

void Employee::setData(int id,string name,int d1,int d2,int d3,int d4,int d5,float wage,float ded)
{
    empID = id;
    empName = name;
    day1 = d1;
    day2 = d2;
    day3 = d3;
    day4 = d4;
    day5 = d5;
    empWage = wage;
    deduction = ded;
}

void Employee::printPayroll()
{
    int totalHour = day1+day2+day3+day4+day5;
    float totalWage = totalHour * empWage;
    float finalWage = totalWage - deduction;
     
        cout<<"  "<<empID<<"\t\t"<<empName<<"\t\t";
        cout<<totalHour<<"\t\t";
        cout<<"$"<<totalWage<<"\t\t";
        cout<<"$"<<deduction<<"\t\t";
        cout<<"$"<<finalWage<<endl;
}

int main()
{
    ifstream in;
    ofstream outPut;
    int newI = 0;
    Employee emp[20];

        //case '1':
        {
            in.open("test.txt");
            int i=0;
            int id, d1, d2, d3, d4, d5;
            float wage, ded;
            string name;

            if(in.is_open())
            {
                while((!in.eof()))
                {
                    in>>id>>name>>d1>>d2>>d3>>d4>>d5>>wage>>ded;
                    emp[i].setData(id,name,d1,d2,d3,d4,d5,wage,ded);
                    emp[i].getData();
                    i++;
                    newI = i;
                }
                cout<<endl;
                in.close();
            }
            else
            {
                cout<<"\n  Unable to open file."<<endl<<endl;
            }
        }
        //break;

        //case '7':
        {
            outPut.open("outputFile.txt");
            {
                if(outPut.is_open())
                {
                   for(int j=0; j<newI; j++)
                    {
                        outPut<<emp[j].printPayroll();
                    }
                }
                else
                cout<<"Nope!";
                outPut.close();
            }
        }
        //break;
return 0;
}

Should I be using something like this in my class?

friend ostream& operator<<(ostream& outPut, const Employee& emp);

ETA: I'm an idiot. I'm sorry. This is the file being read in:

100 Joseph 1 8 3 4 5 13 300.10 
101 John 5 6 7 8 9 12 35.10 
102 Jo 5 4 3 2 1 11 20.10 
103 Johan 8 9 8 7 6 10 25.10 
104 Jacob 7 8 5 6 2 10 20.5
105 Josiah 7 2 6 1 4 13.5 30.10 
106 Jenny 8 6 3 3 5 12.5 32.10 
107 Job 2 2 2 2 2 11.5 10.10 
108 Jane 0 0 0 0 1 10.3 5 
109 Jared 8 8 8 8 8 10.25 20.5

[coder777]

Should I be using something like this in my class?

This is one possible way. It may replace printPayroll().

Another way would be providing ostream to printPayroll():

void Employee::printPayroll(ostream& outPut) const // Note const to use it with a const object
{
    int totalHour = day1+day2+day3+day4+day5;
    float totalWage = totalHour * empWage;
    float finalWage = totalWage - deduction;
     
        outPut<<"  "<<empID<<"\t\t"<<empName<<"\t\t"; // Note: outPut instead of cout
        outPut<<totalHour<<"\t\t";
        outPut<<"$"<<totalWage<<"\t\t";
        outPut<<"$"<<deduction<<"\t\t";
        outPut<<"$"<<finalWage<<endl;
}

You may combine both approaches like so:

friend ostream& operator<<(ostream& outPut, const Employee& emp)
{
  emp.printPayroll(outPut);
  return outPut;
}

[iAqMGNh0]

Thank you so much for your input code777! I took your suggestion and provided ostream to a copy of printPayroll() that I have named outputPayroll() (I have to keep a regular copy of printPayroll() for another section of my program). My updated code looks like this:

void Employee::outputPayroll(ostream& outPut) const object
{
    int totalHour = day1+day2+day3+day4+day5;
    float totalWage = totalHour * empWage;
    float finalWage = totalWage - deduction;

        outPut<<"  "<<empID<<"\t\t"<<empName<<"\t\t";
        outPut<<totalHour<<"\t\t";
        outPut<<"$"<<totalWage<<"\t\t";
        outPut<<"$"<<deduction<<"\t\t";
        outPut<<"$"<<finalWage<<endl;
}

        case '7':
        {
            outPut.open("outputFile.txt");
            {
                if(outPut.is_open())
                {
                    outPut<<"  ID No.\tEmployee Name\tTotal Hours\tSalary\t\tDeduction\tFinal Salary"<<endl;

                    for(int j=0; j<newI; j++)
                    {
                        outPut<<emp[j].outputPayroll(ostream& outPut) const;
                    }
                }
                else
                    cout<<"NOpe!";
                outPut.close();
            }
        }

        break;

I'm sure I'm still not doing the implementation right in the main program and when I compile I get the error report "error: expected primary-expression before '&' token".

However! This is much better than the error report I had before! I will keep looking at my code and see if I can parse this out on my own. I really appreciate your help!

[coder777]

Line 11: outPut<<emp[j].outputPayroll(ostream& outPut) const;

and

void Employee::outputPayroll(ostream& outPut) const object

[keskiverto]

Another approach:

class Employee
{
private:
    int empID;
    string empName;
    int day1, day2, day3, day4, day5;
    float empWage;
    float deduction;
public:
    void setData(int,string,int,int,int,int,int,float,float);
    void getData(void);
    void printMenu();
    void printEmpData();
    void printPayroll( ostream& out = cout ) const;
};

void Employee::printPayroll( std::ostream& out ) const
{
  // printing something to out
}

// The operator does not have to be a friend:
ostream& operator<< ( ostream& outPut, const Employee& emp )
{
  emp.printPayroll( outPut );
  return outPut;
}

Allows:

ofstream ofile( "data.txt" );
Employee bob;
ofile << bob;
bob.printPayroll( ofile );
cout << bob;
bob.printPayroll(); // same as bob.printPayroll( cout ); 

[iAqMGNh0]

Thank you SO SO SO much coder777 and keskiverto! My program now runs perfectly and prints everything to the file.

Here's the updated code for those interested in the changes I made.

class Employee
{
private:
    int empID;
    string empName;
    int day1, day2, day3, day4, day5;
    float empWage;
    float deduction;
public:
    void setData(int,string,int,int,int,int,int,float,float);
    void getData(void);
    void printMenu();
    void printEmpData();
    void outputPayroll( ostream& out = cout ) const;
};

void Employee::outputPayroll( std::ostream& outPut ) const
{
    int totalHour = day1+day2+day3+day4+day5;
    float totalWage = totalHour * empWage;
    float finalWage = totalWage - deduction;

        outPut<<"  "<<empID<<"\t\t"<<empName<<"\t\t"; // Note: outPut instead of cout
        outPut<<totalHour<<"\t\t";
        outPut<<"$"<<totalWage<<"\t\t";
        outPut<<"$"<<deduction<<"\t\t";
        outPut<<"$"<<finalWage<<endl;
}

ostream& operator<< (ostream& outPut, const Employee& emp)
{
  emp.outputPayroll(outPut);
  return outPut;
}

        //case '7':
        {
            ofstream outPut;
            outPut.open("outputFile.txt");
            {
                if(outPut.is_open())
                {
                    outPut<<"  ID No.\tEmployee Name\tTotal Hours\tSalary\t\tDeduction\tFinal Salary"<<endl;
                    for(int j=0; j<newI; j++)
                    {
                        emp[j].outputPayroll(outPut);
                    }
                }
                else
                    cout<<"NOpe!";
                outPut.close();
            }
        }

        //break; 

[keskiverto]

You could replace the emp[j].outputPayroll(outPut);
with outPut << emp[j];