file_exercise

#include <fstream>
#include <iostream>
#include <iomanip>
using namespace std;
#define FILE_TXT "StudentDB.txt"
#define FILE_BIN "StudentDB.dat"
#define MAX_NAME_LEN 50
#define MAX_ID_LEN 7
#define NUM_OF_COURSES 2

typedef struct
{
    char id[MAX_ID_LEN] = { 0 };
    char name[MAX_NAME_LEN] = { 0 };
    double course[NUM_OF_COURSES];
    double GPA;
} Sinhvien;

Sinhvien *record;
int num_of_records;

void readRecord()
{
    cout << "Number of records: ";
    cin >> num_of_records;
    cin.ignore(255, '\n');
    record = new Sinhvien[num_of_records];
    for (int i = 0; i < num_of_records; i++)
    {
        cout << "=========================" << endl;
        cout << "Record " << i + 1 << endl;
        cout << "ID: ";
        cin.get(record[i].id,MAX_ID_LEN);
        cin.ignore(255, '\n');
        cout << "Name: ";
        cin.get(record[i].name, MAX_NAME_LEN);
        cin.ignore(255, '\n');
        for (int j = 0; j < NUM_OF_COURSES; j++)
        {
            cout << "Course " << j + 1 << ": ";
            cin >> record[i].course[j];
            cin.ignore(255, '\n');
        }
        cout << "GPA: ";
        cin >> record[i].GPA;
        cin.ignore(255, '\n');
    }
}

void writeToTxt()
{
    ofstream fout;
    fout.open(FILE_TXT);
    if (fout.is_open())
    {
        fout << "|";
        fout << setw(MAX_ID_LEN + 3) << left << " ID";
        fout << setw(0) << "|";
        fout << setw(MAX_NAME_LEN + 3) << left << " NAME";
        fout << setw(0) << "|";
        for (int i = 0; i < NUM_OF_COURSES; i++)
        {
            fout << setw(3) << " ";
            fout << setw(0) << "|";
        }
        fout << setw(5) << left << " GPA";
        fout << setw(0) << "|" << endl;

        for (int j = 0; j < num_of_records; j++)
        {
            fout << "|";
            fout << setw(MAX_ID_LEN + 3) << right << record[j].id;
            fout << setw(0) << "| ";
            fout << setw(MAX_NAME_LEN + 2) << left << record[j].name;
            fout << setw(0) << "|";
            for (int i = 0; i < NUM_OF_COURSES; i++)
            {
                fout << setw(3) << right << record[j].course[i];
                fout << setw(0) << "|";
            }
            fout << setw(5) << right << record[j].GPA;
            fout << setw(0) << "|" << endl;
        }
        fout.close();
    }
}

void writeToBin()
{
    ofstream fout;
    fout.open(FILE_BIN, ios::binary);
    if (fout.is_open())
    {
        fout.write(reinterpret_cast<char*>(&num_of_records), 4);
        for (int i = 0; i < num_of_records; i++)
        {
            fout.write(record[i].id,MAX_ID_LEN);
            fout.write(record[i].name, MAX_NAME_LEN);
            for (int j = 0; j < NUM_OF_COURSES; j++)
            {
                fout.write(reinterpret_cast<char*>(&record[i].course[j]), sizeof(double));
            }
            fout.write(reinterpret_cast<char*>(&record[i].GPA), sizeof(double));
        }
        fout.close();
    }
}

void readFromBin()
{
    ifstream fin;
    fin.open(FILE_BIN, ios::binary);
    if (fin.is_open())
    {
        fin.read(reinterpret_cast<char*>(&num_of_records), 4);
        record = new Sinhvien[num_of_records];
        for (int i = 0; i < num_of_records; i++)
        {
            fin.read(record[i].id, MAX_ID_LEN);
            fin.read(record[i].name, MAX_NAME_LEN);
            for (int j = 0; j < NUM_OF_COURSES; j++)
            {
                fin.read(reinterpret_cast<char*>(&record[i].course[j]), sizeof(double));
            }
            fin.read(reinterpret_cast<char*>(&record[i].GPA), sizeof(double));
        }

        cout << "|";
        cout << setw(MAX_ID_LEN + 3) << left << " ID";
        cout << setw(0) << "|";
        cout << setw(MAX_NAME_LEN + 3) << left << " NAME";
        cout << setw(0) << "|";
        for (int i = 0; i < NUM_OF_COURSES; i++)
        {
            cout << setw(3) << " ";
            cout << setw(0) << "|";
        }
        cout << setw(5) << left << " GPA";
        cout << setw(0) << "|" << endl;

        for (int j = 0; j < num_of_records; j++)
        {
            cout << "|";
            cout << setw(MAX_ID_LEN + 3) << right << record[j].id;
            cout << setw(0) << "| ";
            cout << setw(MAX_NAME_LEN + 2) << left << record[j].name;
            cout << setw(0) << "|";
            for (int i = 0; i < NUM_OF_COURSES; i++)
            {
                cout << setw(3) << right << record[j].course[i];
                cout << setw(0) << "|";
            }
            cout << setw(5) << right << record[j].GPA;
            cout << setw(0) << "|" << endl;
        }
        fin.close();
    }
}

int main()
{
    readRecord();
    writeToTxt();
    writeToBin();
    delete[] record;
    record = nullptr;
    readFromBin();
    system("pause");
    return 0;
}