I hope I am doing this right, I am a beginner in C and I am having trouble to figure out how to modify an entry. I am doing a phonebook application that will write and record into a text. file. I have finished most of the coding but I just can't modify the contact. Please guide me or show me the way. Thank you.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct Phonebook_Contacts
{
char FirstName[20];
char LastName[20];
char PhoneNumber[20];
} phone;
void AddEntry(phone * );
void DeleteEntry(phone * );
void PrintEntry(phone * );
void SearchForNumber(phone * );
void EditAnEntry(phone * );
void DeleteAll(phone * );
void FreeContacts (phone * );
int counter = 0;
char FileName[256];
FILE *pRead;
FILE *pWrite;
int main (void)
{
phone *phonebook;
phonebook = (phone*) malloc(sizeof(phone)*100);
int iSelection = 0;
if (phonebook == NULL)
{
printf("Out of Memory. The program will now exit");
return 1;
}
else {}
do
{
printf("\t\t**********WELCOME TO TELEPHONE DIRECTORY CONTACT*************");
printf("\n\n\t(1)\tAdd New");
printf("\n\t(2)\tDelete Per Person ");
printf("\n\t(3)\tDisplay Phonebook Entries");
printf("\n\t(4)\tSearch for Phone Number");
printf("\n\t(5)\tModify a contact");
printf("\n\t(6)\tDelete All Entries");
printf("\n\t(7)\tExit Phonebook");
printf("\n\nWhat would you like to do? ");
scanf("%d", &iSelection);
if (iSelection == 1)
{
AddEntry(phonebook);
}
if (iSelection == 2)
{
DeleteEntry(phonebook);
}
if (iSelection == 3)
{
PrintEntry(phonebook);
}
if (iSelection == 4)
{
SearchForNumber(phonebook);
}
if (iSelection == 5)
{
EditAnEntry(phonebook);
}
if (iSelection == 6)
{
DeleteAll(phonebook);
}
if (iSelection == 7)
{
printf("\nYou have chosen to exit the Phonebook.\n");
system("pause");
FreeContacts(phonebook);
return 0;
}
} while (iSelection <= 9);
}
void AddEntry (phone * phonebook)
{
pWrite = fopen("phonebook_contacts.txt", "a");
if ( pWrite == NULL )
{
perror("The following error occurred ");
exit(EXIT_FAILURE);
}
else
{
counter++;
realloc(phonebook, sizeof(phone));
printf("\nFirst Name: ");
scanf("%s", phonebook[counter-1].FirstName);
printf("Last Name: ");
scanf("%s", phonebook[counter-1].LastName);
printf("Phone Number (XXX-XXX-XXXX): ");
scanf("%s", phonebook[counter-1].PhoneNumber);
printf("\n\tFriend successfully added to Phonebook\n");
fprintf(pWrite, "%s\t%s\t%s\n", phonebook[counter-1].FirstName, phonebook[counter-1].LastName, phonebook[counter-1].PhoneNumber);
fclose(pWrite);
}
}
void DeleteEntry (phone * phonebook)
{
int x = 0;
int i = 0;
char deleteFirstName[20]; //
char deleteLastName[20];
printf("\nFirst name: ");
scanf("%s", deleteFirstName);
printf("Last name: ");
scanf("%s", deleteLastName);
for (x = 0; x < counter; x++)
{
if (strcmp(deleteFirstName, phonebook[x].FirstName) == 0)
{
if (strcmp(deleteLastName, phonebook[x].LastName) == 0)
{
for ( i = x; i < counter - 1; i++ )
{
strcpy(phonebook[i].FirstName, phonebook[i+1].FirstName);
strcpy(phonebook[i].LastName, phonebook[i+1].LastName);
strcpy(phonebook[i].PhoneNumber, phonebook[i+1].PhoneNumber);
}
printf("Record deleted from the phonebook.\n\n");
--counter;
return;
}
}
}
printf("That contact was not found, please try again.");
}
void PrintEntry (phone * phonebook)
{
int x = 0;
printf("\nPhonebook Entries:\n\n ");
pRead = fopen("phonebook_contacts.txt", "r");
if ( pRead == NULL)
{
perror("The following error occurred: ");
exit(EXIT_FAILURE);
}
else
{
for( x = 0; x < counter; x++)
{
printf("\n(%d)\n", x+1);
printf("Name: %s %s\n", phonebook[x].FirstName, phonebook[x].LastName);
printf("Number: %s\n", phonebook[x].PhoneNumber);
}
}
fclose(pRead);
}
void SortByFirstName (phone * phonebook)
{
int i = 0;
int x = 0;
int swap;
int TempCounter = counter;
phone Temp;
do
{
swap = 0;
for(i = 1; i < TempCounter; i++)
{
if(strcmp(phonebook[i-1].FirstName, phonebook[i].FirstName) > 0)
{
Temp = phonebook[i];
phonebook[i] = phonebook[i-1];
phonebook[i-1] = Temp;
strcpy(Temp.FirstName, phonebook[i].FirstName);
strcpy(Temp.LastName, phonebook[i].LastName);
strcpy(Temp.PhoneNumber, phonebook[i].PhoneNumber);
swap = 1;
}
}
TempCounter--;
} while (swap);
printf("\nYour friends in Alphabetical Order by First Name:\n\n");
for( x = 0; x < counter; x++ )
{
printf("\n(%d)\n", x+1);
printf("Name: %s %s\n", phonebook[x].FirstName, phonebook[x].LastName);
printf("Number: %s\n", phonebook[x].PhoneNumber);
}
}
void SortByLastName (phone * phonebook)
{
int i = 0;
int x = 0;
int swap;
int TempCounter = counter;
phone Temp;
do
{
swap = 0;
for(i = 1; i < TempCounter; i++)
{
if(strcmp(phonebook[i-1].LastName, phonebook[i].LastName) > 0)
{
Temp = phonebook[i];
phonebook[i] = phonebook[i-1];
phonebook[i-1] = Temp;
strcpy(Temp.FirstName, phonebook[i].FirstName);
strcpy(Temp.LastName, phonebook[i].LastName);
strcpy(Temp.PhoneNumber, phonebook[i].PhoneNumber);
swap = 1;
}
}
TempCounter--;
} while (swap);
printf("\nYour friends in Alphabetical Order by First Name:\n\n");
for( x = 0; x < counter; x++ )
{
printf("\n(%d)\n", x+1);
printf("Name: %s %s\n", phonebook[x].FirstName, phonebook[x].LastName);
printf("Number: %s\n", phonebook[x].PhoneNumber);
}
}
void SearchForNumber (phone * phonebook)
{
int x = 0;
char TempFirstName[20];
char TempLastName[20];
printf("\nPlease type the name of the friend you wish to find a number for.");
printf("\n\nFirst Name: ");
scanf("%s", TempFirstName);
printf("Last Name: ");
scanf("%s", TempLastName);
for (x = 0; x < counter; x++)
{
if (strcmp(TempFirstName, phonebook[x].FirstName) == 0)
{
if (strcmp(TempLastName, phonebook[x].LastName) == 0)
{
printf("\n%s %s's phone number is %s\n", phonebook[x].FirstName, phonebook[x].LastName, phonebook[x].PhoneNumber);
}
}
}
}
void EditAnEntry (phone * phonebook)
{
int c;
FILE *f;
char name[50];
f = fopen("phonebook_contacts.txt", "r+");
if ( f == NULL )
{
perror("The following error occurred ");
exit(EXIT_FAILURE);
}
else
{
printf("\nEnter CONTACT'S NAME TO MODIFY:\n");
counter++;
realloc(phonebook, sizeof(phone));
printf("\nFirst Name: ");
scanf("%s", phonebook[counter-1].FirstName);
printf("Last Name: ");
scanf("%s", phonebook[counter-1].LastName);
printf("Phone Number (XXX-XXX-XXXX): ");
scanf("%s", phonebook[counter-1].PhoneNumber);
printf("\n\tFriend successfully added to Phonebook\n");
fprintf(pWrite, "%s\t%s\t%s\n", phonebook[counter-1].FirstName, phonebook[counter-1].LastName, phonebook[counter-1].PhoneNumber);
fclose(pWrite);
}
}
void DeleteAll (phone * phonebook)
{
int x = 0;
char nullStr[20] = {'\0'};
for ( x = 0; x < counter; x++ )
{
strcpy(phonebook[x].FirstName, nullStr);
strcpy(phonebook[x].LastName, nullStr);
strcpy(phonebook[x].PhoneNumber, nullStr);
--counter;
}
printf("All Contacts have been deleted.\n");
}
void FreeContacts (phone * phonebook)
{
--counter;
for ( ; counter > 0; --counter)
{
free(phonebook[counter].FirstName);
free(phonebook[counter].LastName);
free(phonebook[counter].PhoneNumber);
free(phonebook);
counter = 0;
return;
}
}