Thread: Edit and Delete struct records that are saved in file?

Hey guys,

I am trying to get a few things to work with my code but am unable to get two things within the code to function properly, and wondering if anyone can find a solution that will get it to work.

A basic rundown of the code is that I have two main files that store the information that is saved from a struct. I can add records fine, search for a record, and link the files together, but I am unable to get the editing, or deleting function to work.

Does anyone know how I can edit a record that has been made, and also how to delete a record?

I will be posting the entire code, but the problems lies in the EditSession, DeleteSession, EditChildren, DeleteChildren Parameters.

Thank!

Code:

#include <stdio.h>#include <stdlib.h>
#include <ctype.h>
#include <string.h>


#define TRUE 1
#define FALSE 0
#define CHILDRENFILE "children"
#define SESSIONFILE "sessions"


// child record
struct CHILDDETAILS
{
    char childForename[31];
    char childSurname[31];
    char guardianName[31];
    char guardianNum[12];
    char homeNumber[12];
    int birthDay, birthMonth, birthYear, childID;
    int sessionID;
};


//children record    
struct SESSIONTYPE
{
    int sessionID;
    char sessionName[21];
    char sessionTime[30];
    char sessionDay[15];
    char headOfSession[21];
};


// Prototypes
int SessionToArray(struct SESSIONTYPE *);
void ArrayToSession(int, struct SESSIONTYPE *);
int ChildrenToArray(struct CHILDDETAILS *);
void ArrayToChildren(int, struct CHILDDETAILS *);
int AddSession(int numSessions, struct SESSIONTYPE *);//Add records to borrower file
void DisplaySessions(int numSessions, struct SESSIONTYPE *);//Display all session records
void DisplayOneSession(struct SESSIONTYPE session); //Display individual session record
void SearchSession(int numSessions, struct SESSIONTYPE *);
void EditSession(int numSessions, struct SESSIONTYPE *);
void DeleteSession(int numSessions, struct SESSIONTYPE *);
int AddChildren(int numSessions, int numChildren, struct SESSIONTYPE *, struct CHILDDETAILS *);//Add records to children file
void DisplayChildren(int numSessions, int numChildren, struct SESSIONTYPE *, struct CHILDDETAILS *);//Display all children records
void DisplayOneChild(struct CHILDDETAILS, int numSessions, struct SESSIONTYPE *sessions);//Display individual children record
void SearchChildren(int numSessions, int numChildren, struct SESSIONTYPE *, struct CHILDDETAILS *);
void EditChildren(int numSessions, int numChildren, struct SESSIONTYPE *, struct CHILDDETAILS *);
void DeleteChildren(int numSessions, int numChildren, struct SESSIONTYPE *, struct CHILDDETAILS *);
int Menu();//Main menu
int SessionMenu(int, struct SESSIONTYPE *);//session sub-menu
int ChildMenu(int numSessions, struct SESSIONTYPE *, int numChildren, struct CHILDDETAILS *);//children sub-menu
void EnterSession(int numSessions, struct SESSIONTYPE *sessions); //Enter fields of session record
void EnterChildInfo(int numSessions, int numChildren, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children); //Enter fields of children record
void DisplayThisSession(int sessionID, int numSessions, struct SESSIONTYPE *);//Display single borrower record identified by ID - parameter
void ListSessions(int numSessions, struct SESSIONTYPE *sessions); //Show list of sessions
char ValidQual(); //Enter valid children qualification
void DisplayQual(char qual); //Display children qualification
char ValidYN(); //Function to enter and validate a Y/N reply
int ValidInt(int lower, int upper); //Function to enter and validate an integer in a range
char *ValidateString(int maxLength, char *string);


// Main function
void main()
{
    int choice;
    int numSessions, numChildren;
    //Arrays to store files
    struct SESSIONTYPE sessions[100];
    struct CHILDDETAILS children[100];
    numSessions = SessionToArray(sessions);
    numChildren = ChildrenToArray(children);
    do
    {
        // Call main menu - sessions or children
        choice = Menu();
        switch (choice)
        {
            // Process session file
        case 1: numSessions = SessionMenu(numSessions, sessions);
            break;
            // Process children file
        case 2: numChildren = ChildMenu(numSessions, numChildren, sessions, children);
            break;
            // Quit system    
        case 3: printf("Bye bye\n\n");
            break;
        }
    } while (choice != 3);


    ArrayToSession(numSessions, sessions);
    ArrayToChildren(numChildren, children);
    system("pause");
    exit(0);
}


// Copy session File to session Array
int SessionToArray(struct SESSIONTYPE *sessions)
{
    FILE *fp;
    struct SESSIONTYPE session;
    char reply;
    int numSessions = 0;
    fopen_s(&fp, SESSIONFILE, "rb");
    if (fp == NULL)
    {
        printf("Existing session file not found. Do you want to create a new file? Y/N: ");
        reply = ValidYN();
        if (reply == 'N')
        {
            exit(0);
        }
    }
    else
    {
        // Read first session record
        fread(&session, sizeof(struct SESSIONTYPE), 1, fp);
        //Keep going up to end of file marker 
        while (!(feof(fp)))
        {
            // Copy session read from file to array
            sessions[numSessions] = session;
            //Move to next session in array
            numSessions++;
            // Read subsequent session records 
            fread(&session, sizeof(struct SESSIONTYPE), 1, fp);
        }
        fclose(fp);
    }
    return numSessions;
}


// Copy session Array to session File
void ArrayToSession(int numSessions, struct SESSIONTYPE *sessions)
{
    FILE *fp;
    struct SESSIONTYPE session;
    int i;
    fopen_s(&fp, SESSIONFILE, "wb");
    if (fp == NULL)
    {
        printf("Cannot open session file\n");
        exit(0);;
    }
    for (i = 0; i < numSessions; i++)
    {
        // Write session record in array to file
        fwrite(&sessions[i], sizeof(struct SESSIONTYPE), 1, fp);
    }
    fclose(fp);
}


// Copy children File to children Array
int ChildrenToArray(struct CHILDDETAILS *children)
{
    FILE *fp;
    struct CHILDDETAILS child;
    char reply;
    int numChildren = 0;
    fopen_s(&fp, CHILDRENFILE, "rb");
    if (fp == NULL)
    {
        printf("Existing children file not found. Do you want to create a new file? Y/N: ");
        reply = ValidYN();
        if (reply == 'N')
        {
            exit(0);
        }
    }
    else
    {
        // Read first session record
        fread(&child, sizeof(struct CHILDDETAILS), 1, fp);


        // Keep going up to end of file marker 
        while (!(feof(fp)))


        {
            // Copy children read from file to array
            children[numChildren] = child;
            //Move to next children in array
            numChildren++;
            // Read subsequent session records 
            fread(&child, sizeof(struct CHILDDETAILS), 1, fp);
        }
        fclose(fp);
    }
    return numChildren;
}


// Copy children Array to children File
void ArrayToChildren(int numChildren, struct CHILDDETAILS *children)
{
    FILE *fp;
    struct CHILDDETAILS child;
    int i;
    fopen_s(&fp, CHILDRENFILE, "wb");
    if (fp == NULL)
    {
        printf("Cannot open children file\n");
        exit(0);;
    }
    for (i = 0; i < numChildren; i++)
    {
        // Write session record in array to file
        fwrite(&children[i], sizeof(struct CHILDDETAILS), 1, fp);
    }
    fclose(fp);
}


// Main menu function
int Menu()
{
    int select;
    printf("\n\nWelcome to the Brimsbury Parish Church Little Foxes Toddler Group session management system\n");
    printf("Please select one of the options below: \n\n");
    printf("1: Enter Session information Menu\n2: Enter Children information Menu\n3: Quit system\n\n");
    printf("Enter a number that corresponds to your choice: ");
    select = ValidInt(1, 3);
    printf("\n");
    return select;
}






// Session Menu function
int SessionMenu(int numSessions, struct SESSIONTYPE *sessions)
{
    int choice;
    do
    {
        // Make choice between session file processes
        printf("\n\nYou have entered the Session menu\n");
        printf("This is where you can locate and add information on the Sessions \n\n");
        printf("1: Add a new Session\n2: Display all stored Sessions\n3: Search and display one Session\n4: Edit a Session\n5: Delete a Session\n6: Go Back to the main menu\n\n");
        printf("Enter a number that corresponds to your choice: ");
        choice = ValidInt(1, 6);


        // Do session file processes
        switch (choice)
        {
        case 1: numSessions = AddSession(numSessions, sessions);
            break;
        case 2: DisplaySessions(numSessions, sessions);
            break;
        case 3: SearchSession(numSessions, sessions);
            break;
        case 4: EditSession(numSessions, sessions);
            break;
        case 5: DeleteSession(numSessions, sessions);
            break;
        case 6: ArrayToSession(numSessions, sessions);
            printf("Session file saved\n\n");
            break;
        }
    } while (choice != 6);
    return numSessions;
}


// children Menu function
int ChildMenu(int numSessions, int numChildren, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    int choice;
    do
    {
        printf("\n\nThis is the children sub_system\n");
        printf("You can choose different file handling routines\n\n");
        printf("1: Add a children to file\n2: Display all children on file\n3: Search for a child on file\n4: Edit a child on file\n5: Delete a child on file\n6: Back to main menu\n\n");
        printf("Enter a number that corresponds to your choice: ");
        choice = ValidInt(1, 6);


        // Do children file processes
        switch (choice)
        {
        case 1: numChildren = AddChildren(numSessions, numChildren, sessions, children);
            break;
        case 2: DisplayChildren(numSessions, numChildren, sessions, children);
            break;
        case 3: SearchChildren(numSessions, numChildren, sessions, children);
            break;
        case 4: EditChildren(numSessions, numChildren, sessions, children);
            break;
        case 5: DeleteChildren(numSessions, numChildren, sessions, children);
            break;
        case 6: ArrayToChildren(numChildren, children);
            printf("Children file saved\n\n");
            break;
        }
    } while (choice != 6);
    return numChildren;
}


//Add records to session file
int AddSession(int numSessions, struct SESSIONTYPE *sessions)
{
    //Enter fields of next session record in array
    EnterSession(numSessions, sessions);


    //Increment number of sessions
    numSessions++;
    return numSessions;
}


//Enter fields of session record
void EnterSession(int numSessions, struct SESSIONTYPE *sessions)
{


    printf("Please enter the new Session ID (Format must be between 101 and 999): ");
    sessions[numSessions].sessionID = ValidInt(101, 999);
    printf("Please enter a name for this Session (Up to 50 characters): ");
    strcpy_s(sessions[numSessions].sessionName, 50, ValidateString(50, sessions[numSessions].sessionName));
    printf("Type the day of the week attending (T - Tuesday, W - Wednesday or F - Friday): ");
    strcpy_s(sessions[numSessions].sessionDay, 2, ValidateString(2, sessions[numSessions].sessionDay));
    printf("Please select the time of day this session runs: \n\nM - :Morning (09:30 - 11:00)\nA - :Afternoon (13:30 - 15:00)\n\n");
    strcpy_s(sessions[numSessions].sessionTime, 2, ValidateString(2, sessions[numSessions].sessionTime));
    printf("Enter the initials of the session leader (3 characters): ");
    strcpy_s(sessions[numSessions].headOfSession, 4, ValidateString(4, sessions[numSessions].headOfSession));
}


// Display the whole session file
void DisplaySessions(int numSessions, struct SESSIONTYPE *sessions)
{
    int i;
    printf("Session ID Name                Time of Day       Head of Session  \n");


    // for every record in array
    for (i = 0; i < numSessions; i++)
    {
        DisplayOneSession(sessions[i]);
    }
}




void SearchSession(int numSessions, struct SESSIONTYPE *sessions)
{
    int searchID; //SessionID Search 
    int found = FALSE;
    int i = 0;


    printf("Enter the ID of the session you want to display (101 - 999): ");
    searchID = ValidInt(101, 999);


    //Loop while there are records in the file and student not found
    while ((i < numSessions) && (found == FALSE))
    {
        if (searchID == sessions[i].sessionID)
        {
            //Display student record
            DisplayOneSession(sessions[i]);
            found = TRUE;
        }
        i++;
    }


    if (found == FALSE)
    {
        printf("Session %d is not on file\n", searchID);
    }
    printf("\n\n");




}


void EditSession(int numSessions, struct SESSIONTYPE *sessions)
{
    int editID; //ID to edit   
    int found = FALSE;
    int i = 0;


    printf("Enter the ID of Session you want to edit (101 - 999): ");


    editID = ValidInt(101, 999);


    //Loop while there are records in the file and student not found
    while ((i < numSessions) && (found == FALSE))
    {
        if (editID == sessions[i].sessionID)
        {
            //Display record found
            DisplayOneSession(sessions[i]);
            found = TRUE;


            printf("Enter changed session name (Up to 50 characters): ");
            strcpy_s(sessions[numSessions].sessionName, 50, ValidateString(50, sessions[numSessions].sessionName));


            printf("Enter changed session day (T - Tuesday, W - Wednesday or F - Friday): ");
            strcpy_s(sessions[numSessions].sessionDay, 3, ValidateString(3, sessions[numSessions].sessionDay));


            printf("Enter changed session time M - :Morning (09:30 - 11:00) A - :Afternoon (13:30 - 15:00): ");
            strcpy_s(sessions[numSessions].sessionTime, 2, ValidateString(2, sessions[numSessions].sessionTime));


            printf("Enter changed session Leader (3 characters): ");
            strcpy_s(sessions[numSessions].headOfSession, 3, ValidateString(3, sessions[numSessions].headOfSession));


            //Display updated record
            DisplayOneSession(sessions[i]);
        }
        i++;
    }


    if (found == FALSE)
    {
        printf("Session %d is not on file\n", editID);
    }




    printf("\n\n");
}


void DeleteSession(int numSessions, struct SESSIONTYPE *sessions)
{
    int searchID; //SessionID Search 
    int found = FALSE;
    int i = 0;


    printf("Enter the ID of the Session you want to display (101 - 999): ");
    searchID = ValidInt(101, 999);


    //Loop while there are records in the file and student not found
    while ((i < numSessions) && (found == FALSE))
    {
        if (searchID == sessions[i].sessionID)
        {
            sessions[i].sessionID == 'NULL';
            found = TRUE;
        }
        i++;
    }


    if (found == FALSE)
    {
        printf("Session %d is not on file\n", searchID);
    }
    printf("\n\n");




}


// Display individual session record
void DisplayOneSession(struct SESSIONTYPE session)
{
    printf("\n%-11d%-20s%-20s%-20s\n", session.sessionID, session.sessionName, session.sessionTime, session.headOfSession);
}


// Display one particular session record
// This function finds and displays session of the children you're looking at
// Get ID of matching record thro' parameter passed from children file
void DisplayThisSession(int sessionID, int numSessions, struct SESSIONTYPE *sessions)
{
    int found;
    int i = 0;


    // Matching record not yet found
    found = FALSE;
    //Keep looking while not yet end of file and matching record not yet found
    while ((i < numSessions) && (found == FALSE))
    {
        // Check if this is matching record
        if (sessions[i].sessionID == sessionID)
        {
            // Set flag to show matching record has been found
            found = TRUE;


            // Display details of matching record
            DisplayOneSession(sessions[i]);
        }


        //Move to next session
        i++;
    }


    // If you reach end of array without finding matching record, it's not there
    if (found == FALSE)
    {
        printf("Session not on file\n");
    }
}


//Show list of sessions
void ListSessions(int numSessions, struct SESSIONTYPE *sessions)
{
    int i;
    printf("Session ID Name\n");
    for (i = 0; i < numSessions; i++)
    {
        printf("%-10d %s\n", sessions[i].sessionID, sessions[i].sessionName);
    }
}










// Add records to children file
int AddChildren(int numSessions, int numChildren, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    // Type fields into next children record in array
    EnterChildInfo(numSessions, numChildren, sessions, children);
    //Increment number of children
    numChildren++;
    return numChildren;
}


//Enter child information to store
void EnterChildInfo(int numChildren, int numSessions, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    system("cls");
    printf("Type child ID: (a number between 1 and 90): ");
    children[numChildren].childID = ValidInt(1, 90);


    printf("Type child forename (max length 30 characters): ");
    strcpy_s(children[numChildren].childForename, 30, ValidateString(30, children[numChildren].childForename));


    printf("Type child surname (max length 30 characters): ");
    strcpy_s(children[numChildren].childSurname, 30, ValidateString(30, children[numChildren].childSurname));


    printf("Type child day of birth (in the format DD): ");
    children[numChildren].birthDay = ValidInt(1, 31);


    printf("Type child month of birth (in the format MM): ");
    children[numChildren].birthMonth = ValidInt(1, 12);


    printf("Type child year of birth (in the format YYYY): ");
    children[numChildren].birthYear = ValidInt(1990, 2099);


    printf("Type guardian name (max length 30 characters): ");
    strcpy_s(children[numChildren].guardianName, 30, ValidateString(30, children[numChildren].guardianName));


    printf("Type guardian mobile telephone number (max length 12 numbers): ");
    strcpy_s(children[numChildren].guardianNum, 12, ValidateString(12, children[numChildren].guardianNum));


    printf("Type guardian home telephone number (max length 12 numbers): ");
    strcpy_s(children[numChildren].homeNumber, 12, ValidateString(12, children[numChildren].homeNumber));


    //Children qualification
    printf("Type session ID: \nPossible sessions are:\n");
    ListSessions(numSessions, sessions);
    children[numChildren].sessionID = ValidInt(101, 999);
}


void SearchChildren(int numChildren, int numSessions, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    int searchID; //SessionID Search 
    int found = FALSE;
    int i = 0;


    printf("Enter the ID of the child you want to display (1 - 90): ");
    searchID = ValidInt(1, 90);


    //Loop while there are records in the file and student not found
    while ((i < numChildren) && (found == FALSE))
    {
        if (searchID == children[i].childID)
        {
            //Display student record
            DisplayOneChild(children[i], numSessions, sessions);
            found = TRUE;
        }
        i++;
    }


    if (found == FALSE)
    {
        printf("Session %d is not on file\n", searchID);
    }
    printf("\n\n");




}


void EditChildren(int numChildren, int numSessions, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    int editID; //ID to edit   
    int found = FALSE;
    int i = 0;


    system("cls"); //Clear screen
    printf("Please enter the ID of the child you want to edit: ");
    editID = ValidInt(1, 90);


    while ((i < numChildren) && (found == FALSE)) //Loop while there are records in the file and student not found
    {
        if (editID == children[i].childID)
        {
            DisplayOneChild(children[i], numSessions, sessions); //Displays the record that links to the student ID
            found = TRUE;


            printf("Enter revised day of birth (in the format DD): "); //Enter revised day of birth
            children[i].birthDay = ValidInt(1, 31); //Validates the number


            printf("Enter revised month of birth (in the format MM): "); //Enter revised month of birth
            children[i].birthMonth = ValidInt(1, 12); //Validates the number


            printf("Enter revised month of birth (in the format YYYY): "); //Enter revised month of birth
            children[i].birthMonth = ValidInt(1990, 2099); //Validates the number


            printf("Enter a revised home number: "); //Enter revised home number
            strcpy_s(children[numChildren].homeNumber, 12, ValidateString(12, children[numChildren].homeNumber));


            printf("Enter a revised guardian number: "); //Enter a revised guardian number
            strcpy_s(children[numChildren].guardianNum, 12, ValidateString(12, children[numChildren].guardianNum));


            printf("Enter revised session ID: \nPossible sessions are:\n");
            ListSessions(numSessions, sessions);
            children[numChildren].sessionID = ValidInt(101, 999);


            printf("The revised child record is below.\n\n");


            DisplayOneChild(children[i], numSessions, sessions); //Display edited record
        }
        i++;
    }


    if (found == FALSE) //Child ID not found display error
    {
        printf("Child %d is not on file.\n", editID);
    }


}


void DeleteChildren(int numChildren, int numSessions, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    int searchID; //SessionID Search 
    int found = FALSE;
    int i = 0;


    printf("Enter the ID of the Session you want to display (1 - 90): ");
    searchID = ValidInt(1, 90);


    //Loop while there are records in the file and student not found
    while ((i < numChildren) && (found == FALSE))
    {
        if (searchID == children[i].childID)
        {
            children[i].childID == 'NULL';
            found = TRUE;
        }
        i++;
    }


    if (found == FALSE)
    {
        printf("Session %d is not on file\n", searchID);
    }
    printf("\n\n");




}




// Display the children file
void DisplayChildren(int numSessions, int numChildren, struct SESSIONTYPE *sessions, struct CHILDDETAILS *children)
{
    int i;
    // Keep going for all children
    for (i = 0; i < numChildren; i++)
    {
        if (i == 0)
        {
            printf("-------------------------------------");
        }


        //Display current children details
        DisplayOneChild(children[i], numSessions, sessions);
        printf("-------------------------------------");
    }
}


//Displays one child record
void DisplayOneChild(struct CHILDDETAILS child, int numSessions, struct SESSIONTYPE *sessions)
{
    printf("\nChild ID: %2d\n", child.childID);
    printf("Child forename: %-25s\n", child.childForename);
    printf("Child surname; %-25s\n", child.childSurname);
    printf("Child date of birth: %2d%2d%2d\n", child.birthDay, child.birthMonth, child.birthYear);
    printf("Guardian name: %-25s\n", child.guardianName);
    printf("Guardian mobile number: %-25s\n", child.guardianNum);
    printf("Guardian home number: %-25s\n", child.homeNumber);
    DisplayThisSession(child.sessionID, numSessions, sessions);
}


//Enter and validate Y/N reply
char ValidYN()
{
    char reply;
    do
    {
        scanf_s("%c", &reply, 1);
        fflush(stdin);
        reply = toupper(reply);
    } while ((reply != 'Y') && (reply != 'N'));
    return reply;
}


//Function to enter and validate an integer in a set range
int ValidInt(int lowest, int highest)
{
    int entry;
    do
    {
        scanf_s("%d", &entry);
        fflush(stdin);
        if ((entry < lowest) || (entry > highest))
        {
            printf("Error! Please re-enter\n");
        }
    } while ((entry < lowest) || (entry > highest));
    return entry;
}


char *ValidateString(int MaxLength, char *String1)
{
    String1 = (char *)malloc(80);
    do
    {
        gets_s(String1, 80);
        if (strlen(String1) > MaxLength)
        {
            printf("Error.  String too long. Re-enter\n");
        }
    } while (strlen(String1) > MaxLength);
    return String1;
}

The ChildMenu prototype doesn't match the function definition.

This is triply-wrong:

Code:

sessions[i].sessionID == 'NULL';

== should be =. NULL shouldn't have quotes around it (especially not single quotes!). And it shouldn't even be NULL since sessionID isn't a pointer. There's a similar error elsewhere.