Employ Record Project

The Program Is About Checking, Entering Employ Record In Simple C Language.










#include <stdio.h> ///for input output functions like printf, scanf

#include <stdlib.h>

#include <conio.h>

#include <windows.h> ///for windows related functions (not important)

#include <string.h>  ///string operations

/** List of Global Variable */

COORD coord = {0,0}; /// top-left corner of window

/**

    function : gotoxy

    @param input: x and y coordinates

    @param output: moves the cursor in specified position of console

*/

void gotoxy(int x,int y){

    coord.X = x; coord.Y = y;

    SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),coord);

}

/** Main function started */

int main(){

    FILE *fp, *ft; /// file pointers

    char another, choice;

    /** structure that represent a employee */

    struct emp{

        char name[40]; ///name of employee

        int age; /// age of employee

        float bs; /// basic salary of employee

    };

    struct emp e; /// structure variable creation

    char empname[40]; /// string to store name of the employee

    long int recsize; /// size of each record of employee

    /** open the file in binary read and write mode

    * if the file EMP.DAT already exists then it open that file in read write mode

    * if the file doesn't exit it simply create a new copy

    */

    fp = fopen("EMP.DAT","rb+");

    if(fp == NULL){

        fp = fopen("EMP.DAT","wb+");

        if(fp == NULL){

            printf("Connot open file");

            exit(1);

        }

    }

    /// sizeo of each record i.e. size of structure variable e

    recsize = sizeof(e);

    /// infinite loop continues untile the break statement encounter

    while(1){

        system("cls"); ///clear the console window

        gotoxy(30,10); /// move the cursor to postion 30, 10 from top-left corner

        printf("1. Add Record"); /// option for add record

        gotoxy(30,12);

        printf("2. List Records"); /// option for showing existing record

        gotoxy(30,14);

        printf("3. Modify Records"); /// option for editing record

        gotoxy(30,16);

        printf("4. Delete Records"); /// option for deleting record

        gotoxy(30,18);

        printf("5. Exit"); /// exit from the program

        gotoxy(30,20);

        printf("Your Choice: "); /// enter the choice 1, 2, 3, 4, 5

        fflush(stdin); /// flush the input buffer

        choice  = getche(); /// get the input from keyboard

        switch(choice){

            case '1':  /// if user press 1

                system("cls");

                fseek(fp,0,SEEK_END); /// search the file and move cursor to end of the file

                                        /// here 0 indicates moving 0 distance from the end of the file

                another = 'y';

                while(another == 'y'){ /// if user want to add another record

                    printf("\nEnter name: ");

                    scanf("%s",e.name);

                    printf("\nEnter age: ");

                    scanf("%d", &e.age);

                    printf("\nEnter basic salary: ");

                    scanf("%f", &e.bs);

                    fwrite(&e,recsize,1,fp); /// write the record in the file

                    printf("\nAdd another record(y/n) ");

                    fflush(stdin);

                    another = getche();

                }

                break;

            case '2':

                system("cls");

                rewind(fp); ///this moves file cursor to start of the file

                while(fread(&e,recsize,1,fp)==1){ /// read the file and fetch the record one record per fetch

                    printf("\n%s %d %.2f",e.name,e.age,e.bs); /// print the name, age and basic salary

                }

                getch();

                break;

            case '3':  /// if user press 3 then do editing existing record

                system("cls");

                another = 'y';

                while(another == 'y'){

                    printf("Enter the employee name to modify: ");

                    scanf("%s", empname);

                    rewind(fp);

                    while(fread(&e,recsize,1,fp)==1){ /// fetch all record from file

                        if(strcmp(e.name,empname) == 0){ ///if entered name matches with that in file

                            printf("\nEnter new name,age and bs: ");

                            scanf("%s%d%f",e.name,&e.age,&e.bs);

                            fseek(fp,-recsize,SEEK_CUR); /// move the cursor 1 step back from current position

                            fwrite(&e,recsize,1,fp); /// override the record

                            break;

                        }

                    }

                    printf("\nModify another record(y/n)");

                    fflush(stdin);

                    another = getche();

                }

                break;

            case '4':

                system("cls");

                another = 'y';

                while(another == 'y'){

                    printf("\nEnter name of employee to delete: ");

                    scanf("%s",empname);

                    ft = fopen("Temp.dat","wb");  /// create a intermediate file for temporary storage

                    rewind(fp); /// move record to starting of file

                    while(fread(&e,recsize,1,fp) == 1){ /// read all records from file

                        if(strcmp(e.name,empname) != 0){ /// if the entered record match

                            fwrite(&e,recsize,1,ft); /// move all records except the one that is to be deleted to temp file

                        }

                    }

                    fclose(fp);

                    fclose(ft);

                    remove("EMP.DAT"); /// remove the orginal file

                    rename("Temp.dat","EMP.DAT"); /// rename the temp file to original file name

                    fp = fopen("EMP.DAT", "rb+");

                    printf("Delete another record(y/n)");

                    fflush(stdin);

                    another = getche();

                }

                break;

            case '5':

                fclose(fp);  /// close the file

                exit(0); /// exit from the program

        }

    }

    return 0;

}