C - Using switch() with void()

Question

I want my code to ask user if he/she wants to either add text by using void add() or delete a line by using void delrow() after void list() works, but the code performs both add() and delrow() after asking it. How should I use the switch statement?

Thanks.

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

#define FILENAME_SIZE 128
#define MAX_LINE 2048


void list(){                    // Printing the list.
char filename[100];
printf("\n*** TODO List ***\n ");

FILE *fptr ;
printf("\nPlease enter the file name with its extension: ");
    scanf("%s", filename);
    
    fptr = fopen(filename, "r");

char ch[100];                   // Character limit.
while(fgets(ch,sizeof(ch),fptr)){
  printf("%s",ch);
}
}

void add(){                     // Adding text to list.
char todo[150];                 // Character limit.
char filename[100];
FILE *fptr ;
printf("\n***TODO List - Add ToDo***\n ");
printf("\nPlease enter the file name with its extension:");
    scanf("%s", filename);
    
    fptr = fopen(filename, "a");

printf("\nEnter todo:");          // Getting the text.
scanf("%s",todo);

fprintf(fptr,"\n%s",todo);       // Importing the text.

}

void delrow(){
  
  printf("\n***TODO List - Delete Rows***\n ");
  FILE *fileptr1, *fileptr2;

        char filename[40];
        // File name limit
        char ch;
        int delete_line, temp = 1;

        printf("\nPlease enter the file name with its extension: ");
        scanf("%s", filename);

        //open file in read mode
        fileptr1 = fopen(filename, "r");
        ch = getc(fileptr1);

       while (ch != EOF)
        {
            printf("%c", ch);
            ch = getc(fileptr1);
        }

        //rewind
        rewind(fileptr1);

        printf(" \n Please enter line number of the line to be deleted:");
        scanf("%d", &delete_line);

        //open new file in write mode
        fileptr2 = fopen("temp", "w");

        ch = getc(fileptr1);

        while (ch != EOF)
        {
            ch = getc(fileptr1);
            if (ch == '\n')
                temp++;
                //except the line to be deleted
                if (temp != delete_line)
                {
                    //copy all lines in file replica.c
                    putc(ch, fileptr2);
                }
        }

        fclose(fileptr1);
        fclose(fileptr2);
        remove(filename);

        //rename the file temporary to original name

        rename("temp", filename);

        printf("\n The contents of file after being modified are as follows:\n");

        fileptr1 = fopen(filename, "r");

        ch = getc(fileptr1);

        while (ch != EOF)

        {

            printf("%c", ch);

            ch = getc(fileptr1);

        }

        fclose(fileptr1);
        
}

int main(void) {

int choice=0;
list();
printf("\nPlease state if you want to add todo or delete an existing todo (1:add 2:delete): ");
scanf("%d",&choice);
switch(choice){
case 1:
add();
case 2:
delrow();
default:
printf("\nUnacceptable choice.");
}
  return 0;
}

Answer 1

You must add break statements or your cases will fall through to the one below.

switch (choice) {
    case 1:
        add();
        break;
    case 2:
        delrow();
        break;
    default:
        printf("\nUnacceptable choice.");
}