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Edit the member details

limwn (4)
Hi, I have a binary file called member.bin and I want to read the data from the file and let the user edit the data.
-DATA FROM MEMBER.BIN-
Member Details
---------------------------------------------------------------------
Member ID Name Gender IC Contact Number
---------------------------------------------------------------------
M2002 Chin F 881205-14-1234 013-123 4567
M2004 Chan F 881205-14-1230 013-123 4560

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  #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#pragma warning(disable : 4996)


main() {
	typedef struct { char memberId[6], name[40], gender, IC[15], contactNum[15]; } Member;
	Member members;

	FILE* fPtr;

	//add members
	printf("Add Member Details\n");
	fPtr = fopen("member.bin", "wb");
	char ansEdit;

	do {
		printf("Enter your member ID: ");
		scanf(" %[^\n]", &members.memberId);
		rewind(stdin);
		printf("Enter your name: ");
		scanf(" %[^\n]", &members.name);
		rewind(stdin);
		printf("Enter your gender: ");
		scanf(" %c", &members.gender);
		rewind(stdin);
		printf("Enter your IC: ");
		scanf(" %[^\n]", &members.IC);
		rewind(stdin);
		printf("Enter your contact number: ");
		scanf(" %[^\n]", &members.contactNum);
		fwrite(&members, sizeof(Member), 1, fPtr);

		printf("Member Details\n");
		printf("---------------------------------------------------------------------\n");
		printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
		printf("---------------------------------------------------------------------\n");
		printf("%s\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);

		printf("Do you want to continue adding? (Y/N) ");
		scanf(" %c", &ansEdit);
		ansEdit = toupper(ansEdit);

	} while (ansEdit == 'Y');

	fclose(fPtr);

	//search members
	printf("Search Member Details\n");
	char searchID[6], ansSearch;

	do {
		fPtr = fopen("member.bin", "rb");

		printf("Member ID > ");
		scanf(" %[^\n]", &searchID);
		rewind(stdin);

		printf("Member Details\n");
		printf("---------------------------------------------------------------------\n");
		printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
		printf("---------------------------------------------------------------------\n");

		fread(&members, sizeof(Member), 1, fPtr);

		while (!feof(fPtr)) {

			if (strcmp(searchID, members.memberId) == 0) {

				printf("%s\t\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);
			}
			fread(&members, sizeof(Member), 1, fPtr);
		}

		printf("Do you want to continue searching? (Y/N) ");
		scanf(" %c", &ansSearch);
		ansSearch = toupper(ansSearch);

		fclose(fPtr);

	} while (ansSearch == 'Y');
	
	//modify members
	printf("Modify Member Details\n");

	char ansEdit;
	char arr[20];

	fPtr = fopen("member.bin", "rb");
	fread(&members, sizeof(Member), 1, fPtr);
	while (fread(&members, sizeof(Member), 1, fPtr)) {
		for (int i = 0; i < 20; i++) {
			arr[i] = '\0';

		}

	}
	fclose(fPtr);

	fPtr = fopen("member.bin", "wb");

	do {

		printf("Enter ID of member to view for edit: ");
		scanf(" %[^\n]", &searchID);
		rewind(stdin);

		if (strcmp(searchID, members.memberId) == 0) {

			printf("Enter your name: ");
			scanf(" %[^\n]", &members.name);
			rewind(stdin);
			printf("Enter your gender: ");
			scanf(" %c", &members.gender);
			rewind(stdin);
			printf("Enter your IC: ");
			scanf(" %[^\n]", &members.IC);
			rewind(stdin);
			printf("Enter your contact number: ");
			scanf(" %[^\n]", &members.contactNum);

			fwrite(&members, sizeof(Member), 1, fPtr);

			printf("\n");

			printf("Member Details\n");
			printf("---------------------------------------------------------------------\n");
			printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
			printf("---------------------------------------------------------------------\n");
			printf("%s\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);

		}

		printf("Do you want to continue editing? (Y/N) ");
		scanf(" %c", &ansEdit);
		ansEdit = toupper(ansEdit);

		fclose(fPtr);

	} while (ansEdit == 'Y');

	//display members
	printf("Display Member Details\n");
	fPtr = fopen("member.bin", "rb");

	printf("Member Details\n");
	printf("---------------------------------------------------------------------\n");
	printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
	printf("---------------------------------------------------------------------\n");

	fread(&members, sizeof(Member), 1, fPtr);

	while (!feof(fPtr)) {
		printf("%s\t\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);
		fread(&members, sizeof(Member), 1, fPtr);
	}

	fclose(fPtr); 


	system("pause");
}

However, when I want to edit the data, it came out like this after the searching part

Modify Member Details
Enter ID of member to view for edit: M2002
Do you want to continue editing? (Y/N)

instead of this

Modify Member Details
Enter ID of member to view for edit: M2002
Enter your name: Chin
Enter your gender: F
Enter your IC: 881205-14-1234
Enter your contact number: 012-123 4567
Member Details
---------------------------------------------------------------------
Member ID    Name            Gender        IC        Contact Number
M2002        Chin            F         881205-14-1234   012-123 4567
Do you want to continue editing? (Y/N)

The above output is an example of changing one of the member's data, which is the contact number, from 013-123 4567 to 012-123 4567.
Thank you in advance for your guidance!
salem c (3686)
Your main needs to refactored.

You need three functions to
- add
- search
- edit

With those in place, it's easy to have a main() which just prints a simple 3 choice menu and asks you what to do next.

You also need a function to just input a record from the user.
Then you don't have to copy/paste code from add to edit.

rewind(stdin) probably does nothing useful.
It almost certainly doesn't do what you imagine.

limwn (4)
@salem c
Hi, I had added the functions to my coding. Did you mean something like this?

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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#pragma warning(disable : 4996)

void addMember(struct Member members);
void searchMember(struct Member members);
void modifyMember(struct Member members);
void displayAll(struct Member members);

struct Member { char memberId[6], name[40], gender, IC[15], contactNum[15]; };
FILE* fPtr;


main() {

	struct Member members = { 0 };
	int choice;

	do {
		printf("Member Management System\n");
		printf("-------------------------\n");
		printf("1. Add members info\n");
		printf("2. Search members info\n");
		printf("3. Modify members info\n");
		printf("4. Display all members info\n");
		printf("0. Exit\n");
		printf("Select an option:> ");
		scanf(" %d", &choice);

		switch (choice) {
		case 1:
			addMember(members);
			break;
		case 2:
			searchMember(members);
			break;
		case 3:
			modifyMember(members);
			break;
		case 4:
			displayAll(members);
			break;
		}
	} while (choice != 0);

	printf("Bye Bye!\n");

	system("pause");
}

void addMember(struct Member members) {

	printf("Add Member Details\n");
	fPtr = fopen("member.bin", "wb");

	if (fPtr == NULL) {
		printf("Failed to open file");
		exit(-1);
	}

	char ansEdit;

	do {
		printf("Enter your member ID: ");
		scanf(" %[^\n]", &members.memberId);
		rewind(stdin);
		printf("Enter your name: ");
		scanf(" %[^\n]", &members.name);
		rewind(stdin);
		printf("Enter your gender: ");
		scanf(" %c", &members.gender);
		rewind(stdin);
		printf("Enter your IC: ");
		scanf(" %[^\n]", &members.IC);
		rewind(stdin);
		printf("Enter your contact number: ");
		scanf(" %[^\n]", &members.contactNum);

		fwrite(&members, sizeof(members), 1, fPtr);

		printf("Member Details\n");
		printf("---------------------------------------------------------------------\n");
		printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
		printf("---------------------------------------------------------------------\n");
		printf("%s\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);

		printf("Do you want to continue adding? (Y/N) ");
		scanf(" %c", &ansEdit);
		ansEdit = toupper(ansEdit);

	} while (ansEdit == 'Y');

	fclose(fPtr);

}

void searchMember(struct Member members) {

	printf("Search Member Details\n");
	char searchID[6], ansSearch;

	do {
		fPtr = fopen("member.bin", "rb");
		if (fPtr == NULL) {
			printf("Failed to open file");
			exit(-2);
		}

		printf("Member ID > ");
		scanf(" %[^\n]", &searchID);
		rewind(stdin);

		printf("Member Details\n");
		printf("---------------------------------------------------------------------\n");
		printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
		printf("---------------------------------------------------------------------\n");

		fread(&members, sizeof(members), 1, fPtr);

		while (!feof(fPtr)) {

			if (strcmp(searchID, members.memberId) == 0) {

				printf("%s\t\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);
			}
			fread(&members, sizeof(members), 1, fPtr);
		}

		printf("Do you want to continue searching? (Y/N) ");
		scanf(" %c", &ansSearch);
		ansSearch = toupper(ansSearch);

		fclose(fPtr);

	} while (ansSearch == 'Y');

}

void modifyMember(struct Member members) {
	printf("Modify Member Details\n");

	char ansEdit, searchID[6];
	char arr[20];

	fPtr = fopen("member.bin", "rb");
	if (fPtr == NULL) {
		printf("Failed to open file");
		exit(-3);
	}

	fread(&members, sizeof(members), 1, fPtr);
	while (fread(&members, sizeof(members), 1, fPtr)) {
		for (int i = 0; i < 20; i++) {
			arr[i] = '\0';

		}

	}
	fclose(fPtr);

	fPtr = fopen("member.bin", "wb");
	if (fPtr == NULL) {
		printf("Failed to open file");
		exit(-4);
	}

	do {

		printf("Enter ID of member to view for edit: ");
		scanf(" %[^\n]", &searchID);
		rewind(stdin);

		if (strcmp(searchID, members.memberId) == 0) {

			printf("Enter your name: ");
			scanf(" %[^\n]", &members.name);
			rewind(stdin);
			printf("Enter your gender: ");
			scanf(" %c", &members.gender);
			rewind(stdin);
			printf("Enter your IC: ");
			scanf(" %[^\n]", &members.IC);
			rewind(stdin);
			printf("Enter your contact number: ");
			scanf(" %[^\n]", &members.contactNum);

			fwrite(&members, sizeof(members), 1, fPtr);

			printf("\n");

			printf("Member Details\n");
			printf("---------------------------------------------------------------------\n");
			printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
			printf("---------------------------------------------------------------------\n");
			printf("%s\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);

		}

		printf("Do you want to continue editing? (Y/N) ");
		scanf(" %c", &ansEdit);
		ansEdit = toupper(ansEdit);

		fclose(fPtr);

	} while (ansEdit == 'Y');
}

void displayAll(struct Member members) {
	printf("Display Member Details\n");
	fPtr = fopen("member.bin", "rb");
	if (fPtr == NULL) {
		printf("Failed to open file");
		exit(-5);
	}
	printf("Member Details\n");
	printf("---------------------------------------------------------------------\n");
	printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
	printf("---------------------------------------------------------------------\n");

	fread(&members, sizeof(members), 1, fPtr);

	while (!feof(fPtr)) {
		printf("%s\t\t%s\t\t\t%c\t\t%s\t\t%s\n", members.memberId, members.name, members.gender, members.IC, members.contactNum);
		fread(&members, sizeof(members), 1, fPtr);
	}

	fclose(fPtr);
}

Last edited on
limwn (4)
@salem c
I have some problems with the modify and display part
The program doesn't allow me to modify the member's information

Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 3
Modify Member Details
Enter ID of member to view for edit: M2002
Do you want to continue editing? (Y/N)

It doesn't allow me to change the member's name, IC or contact number.
As for the display part, it doesn't display anything on the console

Display Member Details
Member Details
---------------------------------------------------------------------
Member ID       Name                    Gender          IC              Contact Number
---------------------------------------------------------------------
salem c (3686)
The tricky bit is knowing how to open the file for update mode, and how to use fseek and fflush.
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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#pragma warning(disable : 4996)

struct Member {
  char memberId[6], name[40], gender, IC[15], contactNum[15];
};

void addMember(struct Member members);
void searchMember(struct Member members);
void modifyMember(struct Member members);
void displayAll(struct Member members);
void inputMember(struct Member *members);
void printMemberBanner(void);
void printMember(struct Member members);

int main()
{
  struct Member members = { 0 };
  int choice;

  do {
    printf("Member Management System\n");
    printf("-------------------------\n");
    printf("1. Add members info\n");
    printf("2. Search members info\n");
    printf("3. Modify members info\n");
    printf("4. Display all members info\n");
    printf("0. Exit\n");
    printf("Select an option:> ");
    scanf(" %d", &choice);

    switch (choice) {
    case 1:
      addMember(members);
      break;
    case 2:
      searchMember(members);
      break;
    case 3:
      modifyMember(members);
      break;
    case 4:
      displayAll(members);
      break;
    }
  } while (choice != 0);

  printf("Bye Bye!\n");

  system("pause");
}

void inputMember(struct Member *members)
{
    printf("Enter your member ID: ");
    scanf(" %[^\n]", members->memberId);
    printf("Enter your name: ");
    scanf(" %[^\n]", members->name);
    printf("Enter your gender: ");
    scanf(" %c", &members->gender);
    printf("Enter your IC: ");
    scanf(" %[^\n]", members->IC);
    printf("Enter your contact number: ");
    scanf(" %[^\n]", members->contactNum);
}

void printMemberBanner(void)
{
    printf("Member Details\n");
    printf("---------------------------------------------------------------------\n");
    printf("Member ID\tName\t\t\tGender\t\tIC\t\tContact Number\n");
    printf("---------------------------------------------------------------------\n");
}

void printMember(struct Member members)
{
    printf("%s\t%s\t\t\t%c\t\t%s\t\t%s\n", 
           members.memberId, members.name, members.gender, 
           members.IC, members.contactNum);
}

void addMember(struct Member members)
{
  printf("Add Member Details\n");
  FILE *fPtr = fopen("member.bin", "wb");

  if (fPtr == NULL) {
    printf("Failed to open file");
    exit(-1);
  }

  char ansEdit;
  do {
    inputMember(&members);
    fwrite(&members, sizeof(members), 1, fPtr);

    printMemberBanner();
    printMember(members);

    printf("Do you want to continue adding? (Y/N) ");
    scanf(" %c", &ansEdit);
    ansEdit = toupper(ansEdit);

  } while (ansEdit == 'Y');

  fclose(fPtr);

}

void searchMember(struct Member members)
{
  printf("Search Member Details\n");
  char searchID[6], ansSearch;

  do {
    FILE *fPtr = fopen("member.bin", "rb");
    if (fPtr == NULL) {
      printf("Failed to open file");
      exit(-2);
    }

    printf("Member ID > ");
    scanf(" %[^\n]", searchID);

    printMemberBanner();

    while (fread(&members, sizeof(members), 1, fPtr) == 1) {
      if (strcmp(searchID, members.memberId) == 0) {
        printMember(members);
      }
    }

    printf("Do you want to continue searching? (Y/N) ");
    scanf(" %c", &ansSearch);
    ansSearch = toupper(ansSearch);

    fclose(fPtr);

  } while (ansSearch == 'Y');

}

void modifyMember(struct Member members)
{
  printf("Modify Member Details\n");

  char ansEdit, searchID[6];

  FILE *fPtr = fopen("member.bin", "r+b");
  if (fPtr == NULL) {
    printf("Failed to open file");
    exit(-3);
  }

  do {
    printf("Enter ID of member to view for edit: ");
    scanf(" %[^\n]", searchID);

    rewind(fPtr);   //!! start from the beginning of the file
    while (fread(&members, sizeof(members), 1, fPtr) == 1) {
      if (strcmp(searchID, members.memberId) == 0) {
        inputMember(&members);
        fseek(fPtr, -((long)(sizeof(members))), SEEK_CUR);  //!! step back one record
        fwrite(&members, sizeof(members), 1, fPtr);         //!! write it
        fflush(fPtr);                                       //!! commit it

        printf("\n");

        printMemberBanner();
        printMember(members);
        break; // because member names are unique, no need to search more
      }
    }

    printf("Do you want to continue editing? (Y/N) ");
    scanf(" %c", &ansEdit);
    ansEdit = toupper(ansEdit);
  } while (ansEdit == 'Y');

  fclose(fPtr);
}

void displayAll(struct Member members)
{
  printf("Display Member Details\n");
  FILE *fPtr = fopen("member.bin", "rb");
  if (fPtr == NULL) {
    printf("Failed to open file");
    exit(-5);
  }

  printMemberBanner();

  while ( fread(&members, sizeof(members), 1, fPtr) == 1 ) {
    printMember(members);
  }

  fclose(fPtr);
}



$ ./a.out 
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 1
Add Member Details
Enter your member ID: M1
Enter your name: Fred
Enter your gender: M
Enter your IC: IC1
Enter your contact number: 1234
Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M1	Fred			M		IC1		1234
Do you want to continue adding? (Y/N) y
Enter your member ID: M2
Enter your name: Wilma
Enter your gender: F
Enter your IC: IC2
Enter your contact number: 4321
Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M2	Wilma			F		IC2		4321
Do you want to continue adding? (Y/N) n
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 4
Display Member Details
Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M1	Fred			M		IC1		1234
M2	Wilma			F		IC2		4321
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 2
Search Member Details
Member ID > M1
Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M1	Fred			M		IC1		1234
Do you want to continue searching? (Y/N) n
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 3
Modify Member Details
Enter ID of member to view for edit: M1
Enter your member ID: M1
Enter your name: Barney
Enter your gender: M
Enter your IC: IC3
Enter your contact number: 9999

Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M1	Barney			M		IC3		9999
Do you want to continue editing? (Y/N) n
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 4
Display Member Details
Member Details
---------------------------------------------------------------------
Member ID	Name			Gender		IC		Contact Number
---------------------------------------------------------------------
M1	Barney			M		IC3		9999
M2	Wilma			F		IC2		4321
Member Management System
-------------------------
1. Add members info
2. Search members info
3. Modify members info
4. Display all members info
0. Exit
Select an option:> 0
Bye Bye!
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