C Create an EmployeeDemo class It includes three functions 1

C#

Create an “EmployeeDemo” class. It includes three functions:

1. In the main function, the program calls the readData() function to get the data from file and calls the objSort() function to sort the array of objects. Then, the program prompts user to enter the range of current salary that user want to see and display the employee’s information whose current salary is in the range in a descending order.

2. readData(): it reads the workers and managers information from files (“worker.txt” and “manager.txt”) and then creates the dynamic arrays of objects to save the data. Then, it prompts user for the current year to calculate the yearWorked and currentSalary.

3. objSort(): this function accepts an array of object as a parameter and sort the array by current salary in descending order.

Solution

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#define size 200

struct emp

{

    int id;

    char *name;

}*emp1, *emp3;

void display();

void create();

void update();

FILE *fp, *fp1;

int count = 0;

void main(int argc, char **argv)

{

    int i, n, ch;

    printf(\"1] Create a Record\ \");

    printf(\"2] Display Records\ \");

    printf(\"3] Update Records\ \");

    printf(\"4] Exit\");

    while (1)

    {

        printf(\"\ Enter your choice : \");

        scanf(\"%d\", &ch);

        switch (ch)

        {

        case 1:   

            fp = fopen(argv[1], \"a\");

            create();

            break;

        case 2:   

            fp1 = fopen(argv[1],\"rb\");

            display();

            break;

        case 3:   

            fp1 = fopen(argv[1], \"r+\");

            update();

            break;

        case 4:

            exit(0);

        }

    }

}

/* To create an employee record */

void create()

{

    int i;

    char *p;

    emp1 = (struct emp *)malloc(sizeof(struct emp));

    emp1->name = (char *)malloc((size)*(sizeof(char)));

    printf(\"Enter name of employee : \");

    scanf(\" %[^\ ]s\", emp1->name);

    printf(\"Enter emp id : \");

    scanf(\" %d\", &emp1->id);

    fwrite(&emp1->id, sizeof(emp1->id), 1, fp);

    fwrite(emp1->name, size, 1, fp);

    count++;   // count to number of entries of records

    fclose(fp);

}

/* Display the records in the file */

void display()

{   

    emp3=(struct emp *)malloc(1*sizeof(struct emp));   

    emp3->name=(char *)malloc(size*sizeof(char));

    int i = 1;

    if (fp1 == NULL)   

        printf(\"\ File not opened for reading\");

    while (i <= count)

    {

        fread(&emp3->id, sizeof(emp3->id), 1, fp1);

        fread(emp3->name, size, 1, fp1);

        printf(\"\ %d %s\",emp3->id,emp3->name);

        i++;

    }

    fclose(fp1);

    free(emp3->name);

    free(emp3);

}

void update()

{

    int id, flag = 0, i = 1;

    char s[size];

    if (fp1 == NULL)

    {

        printf(\"File cant be opened\");

        return;

    }

    printf(\"Enter employee id to update : \");

    scanf(\"%d\", &id);

    emp3 = (struct emp *)malloc(1*sizeof(struct emp));

        emp3->name=(char *)malloc(size*sizeof(char));

    while(i<=count)

    {   

        fread(&emp3->id, sizeof(emp3->id), 1, fp1);

        fread(emp3->name,size,1,fp1);

        if (id == emp3->id)

        {

            printf(\"Enter new name of emplyee to update : \");   

            scanf(\" %[^\ ]s\", s);

            fseek(fp1, -204L, SEEK_CUR);

            fwrite(&emp3->id, sizeof(emp3->id), 1, fp1);

            fwrite(s, size, 1, fp1);

            flag = 1;

            break;

        }

        i++;

    }

    if (flag != 1)

    {

        printf(\"No employee record found\");

        flag = 0;

    }

    fclose(fp1);

    free(emp3->name);        /* to free allocated memory */

    free(emp3);

}