Database.cpp

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <conio.h>
#include <iomanip>
using namespace std;
int main()
{
    FILE *fp, *ft;
    int i;
    char another, choice;
    struct student
    {
        char first_name[50],last_name[50];
        char course[100];
        char section;
    };
    struct student e;
    char xfirst_name[50],xlast_name[50];
    long int recsize;
    fp=fopen("users.txt","rb+");
    if (fp == NULL)
    {
        fp = fopen("users.txt","wb+");
        if (fp==NULL)
        {
            puts("Cannot open file");
            return 0;
        }
    }
    recsize = sizeof(e);
    while(1)
    {
        system("cls");
        cout << "\n \t\t\t Press 1 to add records";
        cout << "\n \t\t\t Press 2 to display records";
        cout << "\n \t\t\t Press 3 to modify records";
        cout << "\n \t\t\t Press 4 to delete records";
        cout << "\n \t\t\t Press 5 to exit program";
        cout << "\n\n";
        cout << "\t\t\t Enter your choice : ";
        fflush(stdin);
        choice = getche();
        switch(choice)
        {
        case '1' :
            fseek(fp,0,SEEK_END);
            another ='Y';
        	while(another == 'Y' || another == 'y')
            {
                system("cls");
                cout << "Enter the First Name : ";
                cin >> e.first_name;
                cout << "Enter the Last Name : ";
                cin >> e.last_name;
                cout << "Enter the Course    : ";
                cin >> e.course;
                cout << "Enter the Section   : ";
                cin >> e.section;
                fwrite(&e,recsize,1,fp);
                cout << "\n Add Another Record (Y/N) ";
                fflush(stdin);
                another = getchar();
            }
            break;
        case '2':
            system("cls");
            rewind(fp);
            cout << "Saved Records:";
            while (fread(&e,recsize,1,fp) == 1)
            {
                cout << "\n";
                cout<<"Firstname      Lastname";
                cout <<"\n"<<e.first_name<<"\t\t"<<e.last_name<<"\n";
             	cout<<"Course\tSection";
                cout <<"\n" <<e.course<<"\t"<<e.section;
            }
            cout << "\n\n";
            system("pause");
            break;
        case '3' :
            system("cls");
            another = 'Y';
            while (another == 'Y'|| another == 'y')
            {
                cout << "\n Enter the last name of the student : ";
                cin >> xlast_name;
                rewind(fp);
                if (fread(&e,recsize,1,fp) == 1)
                {
                    if (strcmp(e.last_name,xlast_name) == 0)
                    {
                        cout << "Enter new the Firt Name : ";
                        cin >> e.first_name;
                        cout << "Enter new the Last Name : ";
                        cin >> e.last_name;
                        cout << "Enter new the Course    : ";
                        cin >> e.course;
                        cout << "Enter new the Section   : ";
                        cin >> e.section;
                        fseek(fp, - recsize, SEEK_CUR);
                        fwrite(&e,recsize,1,fp);
                        break;
                    }
                    else
                        cout<<"record not found";
                }
                cout << "\n Modify Another Record (Y/N) ";
                fflush(stdin);
                another = getchar();
            }
            break;
        case '4':
            system("cls");
            another = 'Y';
            while (another == 'Y'|| another == 'y')
            {
                cout << "\n Enter the last name of the student to delete : ";
                cin >> xlast_name;
                ft = fopen("temp.dat", "wb");
                rewind(fp);
                if(fread (&e, recsize,1,fp) == 1){
                    if (strcmp(e.last_name,xlast_name) != 0)
                    {
                        fwrite(&e,recsize,1,ft);
                    }
                fclose(fp);
                fclose(ft);
                remove("users.txt");
                rename("temp.dat","users.txt");
                fp=fopen("users.txt","rb+");
                }
                else
                	cout<<"Name cannot be found.";
                cout << "\n Delete Another Record (Y/N) ";
                fflush(stdin);
                another = getchar();
            }
            break;
        case '5':
            fclose(fp);
            cout << "\n\n";
            cout << "\t\t\t\t BYE BYE .";
            exit(0);
        }
    }
   getch();
    return 0;
}