/* v_regdb.c ****************************************************************/
/* */
/* */
/* */
/* This is a maintenance program for an existing Vehicle Database. */
/* The program is an interactive menu system, which allows the user to */
/* edit, delete and insert records into an existing database. */
/* All input is validated with any relevent error messages, should an */
/* error occur. In the event of an error the input is not written to file */
/* and the user is returned to the Main Menu screen. */
/* */
/* */
/* */
/****************************************************************************/
/* Header files *************************************************************/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <conio.h>
#include <ctype.h>
#include <time.h>
#define FILENAME "VREGDB.DAT"/* This is the actual file used - */
/* initialized & working (26000 records) */
/* record no. 000 - 25999. */
/*Structure Declarations ****************************************************/
/********************************************************/
struct t_date{ /* tag ~ t_date stores the tempory date & checks if a */
/* specific file has existing data or not . */
int temp_day; /* format DD. */
int temp_month; /* format MM. */
}temp_date; /* var temp_date is declared as an instace of struct */
/* t_date. */
/********************************************************/
/*********************************************/
struct date{ /* tag ~ date stores the actual date. */
int day; /* format DD. */
int month; /* format MM. */
}; /*********************************************/
/*********************************************/
struct pnc{ /*tag ~ pnc stores the main data input. */
int RecNo; /* Record Number. */
char V_RegNo [8]; /* Vehicle Registration Number. */
struct date V_Regdate; /* struct of type date. */
char V_Maker [11]; /* Vehicle Manufacturer. */
char V_Model [11]; /* Vheicle Model. */
char V_Colour [9]; /* Vehicle Colour. */
char V_Owner [26]; /* Vehicle Owners Name. */
char V_Address[31]; /* Vehicle Owners Address. */
struct date V_Expiry; /* struct of type date. */
}vehicle; /* var vehicle is declared as an instance */
/* of struct pnc. */
/*********************************************/
/*Function Declarations *****************************************************/
/*********************************************/
int validate_VReg(char *reg); /* Validates The Vehicle Reg Format & returns*/
/* an error message or a valid Record Number */
void error_scr(char *reason, int delay);/* Dislays any errors on the screen */
void gotoxy(int col, int row); /* Mainly used for screen positioning */
void clrscr(void); /* Used to clear screen between displays */
void pause_msg(int ln_x, int ln_y,char *msg, int delay);/*Displays a message*/
/* on the screen for a given length of time. */
void input_details(void); /*Inputs data from the user. */
/*********************************************/
/*Globle Variables **********************************************************/
/*********************************************/
int ch,flag,recno;
char temp_regno[8],choice, Str;
int ESC = 27; /* Esc Used to escape or end program */
FILE *fp; /* Pointer to FILE */
/**********************************************/
/*Star of Main **************************************************************/
void main()
{
/* Test to see if the file exists and it can be opened in read mode.
If an error is detected print a message & terminate the program. */
if((fp=fopen(FILENAME,"rb"))==NULL)
{
error_scr("ERROR ! READING FILE!", 3);
exit(1);
}
while(1) /* Start of infinate loop */
{
/* Start of main menu with a list of choises*/
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%20sMAIN MENU%21s||","","","");
printf("\n%14s\\\\________________________________________________//","");
printf("\n\n\n%30s1 : Add New Vehicle"
"\n\n%30s2 : Edit Details"
"\n\n%30s3 : Delete Entry"
"\n\n%28sESC : Exit [ ] ","","","","");
gotoxy(51,13);
choice = getch();
switch(choice)
{
case '1' :/*If 1 is chosen then Add Vehicle Details page is displayed*/
{
clrscr();
if((fp=fopen(FILENAME,"wb"))==NULL)
{
error_scr("ERROR ! READING FILE!", 3);
exit(1);
}
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%15sADD VEHICLE DETAILS%16s||","","","");
printf("\n%14s\\\\________________________________________________//","");
gotoxy(18,7);printf("Enter Vehicle Reg No. : ");
gets(vehicle.V_RegNo);
/* Flags are use mostley in validate_VReg() Function to determin wheather a
specific event has taken place. If so they are set again within Validate_VReg()
in order to inform the program how to execute the rest of the statements in
case '1': i.e. If an error is detcted while in the validation process an
error message is displayed control is returned to main(); */
flag=0;
validate_VReg(vehicle.V_RegNo);
if(flag==1)
break; /*Return to main menu */
input_details();
/* The user is asked if they wish to add the new record. If they dont choose
the letter y A message is displayed and the user is returned to the main menu.
If y is chosen the record is added. */
gotoxy(18,16); printf("Are you sure you want to INSERT this record [ ]");
gotoxy(65,16);
ch=toupper(getch());
if(ch != 'Y')
{
pause_msg(32,17,"RECORD NOT INSERTED!",3);
break; /*Return to main menu */
}
fread(&vehicle,sizeof(vehicle),1,fp); /* Read the file */
/* Check if the record exists. Write it to file if it dosent exist else display
a message. */
if(vehicle.V_Regdate.day == 99 || vehicle.V_Regdate.month == 99)
{
vehicle.V_Regdate.day=temp_date.temp_day ;
vehicle.V_Regdate.month=temp_date.temp_month;
fwrite(&vehicle,sizeof(vehicle),1,fp);
pause_msg(32,17,"RECORD ADDED!",3);
break; /*Return to main menu */
}
else
{
error_scr("A RECORD ALLREADY EXISTS!",3);
break; /*Return to main menu */
}
}
case '2' :/*If 2 is chosen then ammend Vehicle Details page is displayed*/
{
clrscr();
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%14sAMMEND VEHICLE DETAILS%14s||","","","");
printf("\n%14s\\\\________________________________________________//","");
gotoxy(18,7);printf("Enter Vehicle Reg No. : ");
gets(vehicle.V_RegNo);
flag=1;
validate_VReg(vehicle.V_RegNo); /*Validate the registration number*/
if(flag==1) /*flag is set to 1 if an error occured*/
break; /*Return to main menu */
/*Test to see if the record exists, if not display a message*/
if((vehicle.V_Regdate.day == 99) && (vehicle.V_Regdate.month== 99))
{
pause_msg(32,17,"RECORD DOSE NOT EXIST!",3);
break; /*Return to main menu */
}
flag=0;
/*If the record exists input all the details*/
input_details();
/*Get confirmation before ammending the record*/
gotoxy(18,16);printf("Are you sure you want to AMMEND this record [ ]");
gotoxy(65,16);ch=toupper(getch());
if(ch != 'Y')
{
pause_msg(32,17,"RECORD NOT AMMENDED!",3);
break; /*Return to main menu */
}
/* The record is then written, and confirmation
is displayed*/
fwrite(&vehicle,sizeof(vehicle),1,fp);
pause_msg(32,17,"RECORD AMMENDED!",3);
break; /*Return to main menu */
}
case '3' :/*If 3 is chosen then delete Vehicle Details page is displayed*/
{
clrscr();
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%14sDELETE VEHICLE DETAILS%14s||","","","");
printf("\n%14s\\\\________________________________________________//","");
gotoxy(18,7);printf("Enter Vehicle Reg No. : ");
gets(temp_regno);
flag=0;
validate_VReg(temp_regno);
if(flag==1)
break; /*Return to main menu */
/*A warning message is displayed on the screen and the user is prompted for
confirmation to delete the record*/
gotoxy(35,9);printf("WARNING!!");
gotoxy(18,10);printf("Are you sure you want to DELETE this record [ ]");
gotoxy(65,10); ch=toupper(getch());
if(ch != 'Y')
{
pause_msg(32,17,"RECORD NOT DELETED!",3);
break; /*Return to main menu */
}
fread(&vehicle,sizeof(vehicle),1,fp);
if(vehicle.V_Regdate.day==99 && vehicle.V_Regdate.month==99)
{
error_scr("REG NO.DOESN'T EXIST",3);
break; /*Return to main menu */
}
/*If the record exists change the dates to 99 & write it to disc*/
vehicle.V_Regdate.day=99 ;
vehicle.V_Regdate.month=99;
fwrite(&vehicle,sizeof(vehicle),1,fp);
pause_msg(32,17,"RECORD DELETED!",3);
break; /*Return to main menu */
}
/* If the Esc button is pressed the program terminates normally after displaying
the exit screen*/
case 27 :
{
fclose(fp); /*Close the opened file*/
clrscr();
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%15sPROGRAM TERMINATED%17s||","","","");
printf("\n%14s\\\\________________________________________________//","");
printf("\n\n\n%20sThank You for using this Vehicle Database!"
"\n\n\n\n%31sProgrammer : K.Angel"
"\n\n\n%38s2005.","","","","","","","");
exit(0); /* Normal termination of the program */
break; /*This break is never reached */
}
default : /* If an invalid choise was made a message is displayed*/
error_scr("INVALID CHOICE!",2); /*Return to main menu after running
/*error message */
}
}
}
/************************************************************** End of Main */
/* Functions ****************************************************************/
/****************************************************************************/
/* Func ~ */
/* int validate_vReg( char *reg); */
/* ============================== */
/* This function is used to validate the format of the vehicle */
/* registration input by the user. */
/* It also creates a unique record number which is used to */
/* calculate the offset for the file pointer positioning. */
/* The record size (sizeof(vehicle)) is multiplied by the record */
/* number to give the offset from the begining of the file */
/* (SEEK_SET). */
/* The file pointer is tested to see if it is starting off at */
/* position 0. The program will terminate with an error message */
/* if the statement is not true. */
/*Arguments~ */
/* A string (vehicle regitration number) input by the user is */
/* passed to the function. */
/*Returns ~ */
/* nill */
/****************************************************************************/
int validate_VReg(char *reg)
{
/*Local variable ~ only visable within Func validate_VReg();*/
char *str, *str_ptr=vehicle.V_RegNo;
int j=0, x=0, i=0;
while(i<7)
{
/*Test Format of the Registration number*/
if((!isalpha(reg[0]))||(!isdigit(reg[1]))||
(!isdigit(reg[2]))||(!isdigit(reg[3]))||
(!isalpha(reg[4]))||(!isalpha(reg[5]))||
(!isalpha(reg[6])))
{
/*If an error is detected print an error message and set the flag to 1 to
inform the next program executable statement that an error has occured*/
error_scr("ERROR - Invalid Reg Format", 2);
flag = 1;
return (0);
}
/*If no error in the file format. Convert the first Charater to uppercase*/
if(i==0)
{
ch = toascii(reg[0]);
ch=toupper(ch);
str_ptr++;
}
/*Covert the character into its integer value*/
if(i==1)
{ str = str_ptr;
j= atoi(str);
}
i++;
}
/*Formula to create th record number*/
x = ch - 65;
recno = (x * 1000) + j;
/*Move the fp to the correct possition & test it if an error is detected display
an error message and terminate the program*/
if(fseek(fp,(recno * sizeof(vehicle)),SEEK_SET)!=0)
{
error_scr("FILE READ ERROR! EXITING PROGRAM",4);
exit(1);
}
/*The flag is set to 0 in Add case 1 so at this point the program will continue
to execute passed this flag test. In case 2 the flag is set to 1 so at this
flag test the program returns to main(). The flag is reset to 0 to indecate
no errors occured*/
if(flag == 1)
{
flag=0;
return(0);
}
/*Display the vehicle record number only in case 1 as case 2 never
reaches here*/
gotoxy(18,5);printf("VEHICLE RECORD NUMBER : %d", recno);
vehicle.RecNo = recno;
return(0);
}
/********************************************** End of Func validate_VReg() */
/****************************************************************************/
/* Func ~ */
/* void error_scr(char *msg, int delay); */
/* ===================================== */
/* This function displays a message under the title ERROR for a */
/* short period of time. The message is displayed through a */
/* seperate function call. */
/*Arguments~ */
/* There are two arguments passed to this function. */
/* First is a string which is used to dislay the appopriate */
/* message on the screen. */
/* The second argument is used to store a number wich determins */
/* the length of time to display the message. */
/*Returns ~ */
/* void. */
/****************************************************************************/
void error_scr(char *msg, int delay)
{
clrscr();
printf("\n%14s//¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯\\\\","");
printf("\n%13s||%21sERROR!%23s||","","","");
printf("\n%14s\\\\________________________________________________//","");
pause_msg(30,9,msg,delay); /*Display a message*/
}
/************************************************** End of Func error_scr() */
/****************************************************************************/
/* Func ~ */
/* void pause_msg(int ln_x, int ln_y,char *msg, int delay); */
/* ======================================================== */
/* This function displays a message on the screen for a given */
/* amount of time. */
/* It uses the standard C function time() & is measured in seconds.*/
/*Arguments~ */
/* There are four arguments passed to this function. */
/* 1. int ln_x & int ln_y position the message on screen. */
/* 3. char *msg the actual message. */
/* 4. int delay the length of time to display the message. */
/*Returns~ */
/* void. */
/****************************************************************************/
void pause_msg(int ln_x, int ln_y,char *msg, int delay)
{
time_t start;
time_t current;
time(&start);
gotoxy(ln_x,ln_y);printf(msg);fflush(stdin);
do
{
time(¤t);
}
while(difftime(current,start) < delay);
clrscr();
}
/**************************************************** End of Func pause_msg */
/****************************************************************************/
/* Func ~ */
/* void input_details(void); */
/* ========================= */
/* This function allows the user to input data to store. */
/* It's a simple function that cuts down on repetative coding */
/*Arguments~ */
/* void */
/*Returns ~ */
/* void */
/****************************************************************************/
void input_details(void)
{
gotoxy(24,8); printf("Reg Date DD/MM : ");
scanf("%d%[ -/.,\n]%d",&temp_date.temp_day,&Str, &temp_date.temp_month);
fflush(stdin);
gotoxy(24,9); printf("Vehicle Make : ");
gets(vehicle.V_Maker);
gotoxy(24,10); printf("Model : ");
gets(vehicle.V_Model);
gotoxy(24,11); printf("Colour : ");
gets(vehicle.V_Colour);
gotoxy(24,12); printf("Owners Name : ");
gets(vehicle.V_Owner);
gotoxy(24,13); printf("Address : ");
gets(vehicle.V_Address);
gotoxy(22,14); printf("Expiry Date DD/MM : ");
scanf("%2d%[ -/.,\n]%2d",&vehicle.V_Expiry.day,&Str,&vehicle.V_Expiry.month);
fflush(stdin);
}
/********************************************** End of Func input_details() */
/********************************************************* End of Functions */
Please don't post any length of code without using code tags. -Narue
:?:
