add: cpp-programming-questions 14_file_handling 09

Author: webwithaman

14_file_handling/07_store_book/store_book.cpp

@@ -49,7 +49,7 @@ class Book
     }
 
     // // instance member function to get bookId
-    unsigned int getBookId()
+    unsigned int getBookId() const
     {
         return bookId;
     }
@@ -61,7 +61,7 @@ class Book
     }
 
     // // instance member function to get bookTitle
-    const char *getBookTitle()
+    const char *getBookTitle() const
     {
         return bookTitle;
     }
@@ -73,13 +73,13 @@ class Book
     }
 
     // // instance member function to get bookPrice
-    double getBookPrice()
+    double getBookPrice() const
     {
         return bookPrice;
     }
 
     // // instance member function to input and set book data
-    void inputBookData()
+    void inputBookData() 
     {
         int bookId;
         char bookTitle[Book::MAX_CHARS_IN_TITLE];
@@ -105,15 +105,15 @@ class Book
     }
 
     // // instance member function to show book data
-    void showBookData()
+    void showBookData() const
     {
         cout << "\nBook Id => " << bookId;
         cout << "\nBook Title => " << bookTitle;
         cout << "\nBook Price => " << bookPrice;
     }
 
     // // instance member function to store book record
-    int storeBookData()
+    int storeBookData() const
     {
         if (bookId == -1 || bookPrice == -1)
             return 0; // book data not stored
@@ -138,7 +138,7 @@ class Book
 };
 
 // // function to fetch books data from a fike and show
-void fetchAndShowBookData()
+void fetchAndShowBookData() 
 {
     // // specify file name
     const char *fileName = "books_data.dat";

14_file_handling/employee_data/employee_data.cpp

@@ -0,0 +1,330 @@
+/*
+
+A company has following details of their employees in the file 'emp.dat'
+a. Emp Id
+b. Emp Name
+c. Emp Address
+d. Emp Dept (Admin/Sales/Production/IT)
+e. Emp Phone
+f. Emp Age
+
+Write a C++ program to read the above file. Create a new file such as adm.dat,
+sal.dat, pro.dat, IT.dat respectively to store the employee details according to their department.
+
+*/
+
+// // Header files
+#include <iostream>
+#include <fstream>
+#include <cstring>
+
+// // use namespace
+using namespace std;
+
+#define MAX_BOOKS 50
+
+// // define class Employee
+class Employee
+{
+public:
+    // // static member variables
+    static const unsigned int MAX_CHARS_IN_ADDRESS = 51;
+    static const unsigned int MAX_CHARS_IN_NAME = 31;
+    static const unsigned int MAX_CHARS_IN_DEPARTMENT = 31;
+    static const unsigned int MAX_CHARS_IN_PHONE = 11;
+
+private:
+    // // instance member variables
+    unsigned int id, age;
+    char name[MAX_CHARS_IN_NAME], address[MAX_CHARS_IN_ADDRESS], department[MAX_CHARS_IN_DEPARTMENT], phone[MAX_CHARS_IN_PHONE];
+
+public:
+    // // constructors
+    Employee()
+    {
+        id = -1;
+        age = -1;
+        name[0] = 0;
+        address[0] = 0;
+        department[0] = 0;
+        phone[0] = 0;
+    }
+
+    Employee(int id, const char *name, int age, const char *phone, const char *address, const char *department)
+    {
+        this->id = id;
+        this->age = age;
+        strcpy(this->name, name);
+        strcpy(this->phone, phone);
+        strcpy(this->address, address);
+        strcpy(this->department, department);
+    }
+
+    // // instance member function to set id
+    void setId(int id)
+    {
+        if (id < 0) // if id is negative make it positive
+            id = -id;
+
+        this->id = id;
+    }
+
+    // // instance member function to get id
+    unsigned int getId()
+    {
+        return id;
+    }
+
+    // // instance member function to set age
+    void setAge(int age)
+    {
+        if (age < 0) // if age is negative make it positive
+            age = -age;
+
+        this->age = age;
+    }
+
+    // // instance member function to get age
+    unsigned int getAge()
+    {
+        return age;
+    }
+
+    // // instance member function to set name
+    void setName(const char *name)
+    {
+        strcpy(this->name, name);
+    }
+
+    // // instance member function to get name
+    const char *getName()
+    {
+        return name;
+    }
+
+    // // instance member function to set phone
+    void setPhone(const char *phone)
+    {
+        strcpy(this->phone, phone);
+    }
+
+    // // instance member function to get phone
+    const char *getPhone()
+    {
+        return phone;
+    }
+
+    // // instance member function to set address
+    void setAddress(const char *address)
+    {
+        strcpy(this->address, address);
+    }
+
+    // // instance member function to get address
+    const char *getAddress()
+    {
+        return address;
+    }
+
+    // // instance member function to set department
+    void setDepartment(const char *department)
+    {
+        strcpy(this->department, department);
+    }
+
+    // // instance member function to get department
+    const char *getDepartment()
+    {
+        return department;
+    }
+
+    // // instance member function to input and set employee data
+    void inputEmployeeData()
+    {
+        int empId;
+        char bookTitle[Employee::MAX_CHARS_IN_TITLE];
+        double bookPrice;
+
+        // // Get book id
+        cout << "\nEnter Employee Id => ";
+        cin >> empId;
+
+        // // Get book title
+        cout << "\nEnter Employee Title (MAX_CHARS " << Employee::MAX_CHARS_IN_TITLE - 1 << ") => ";
+        cin.ignore();
+        cin.getline(bookTitle, Employee::MAX_CHARS_IN_TITLE);
+
+        // // Get book price
+        cout << "\nEnter Employee Price => ";
+        cin >> bookPrice;
+
+        // // set data
+        setEmployeeId(empId);
+        setEmployeeTitle(bookTitle);
+        setEmployeePrice(bookPrice);
+    }
+
+    // // instance member function to show book data
+    void showEmployeeData()
+    {
+        cout << "\nEmployee Id => " << empId;
+        cout << "\nEmployee Title => " << bookTitle;
+        cout << "\nEmployee Price => " << bookPrice;
+    }
+
+    // // instance member function to store book record
+    int storeEmployeeData()
+    {
+        if (empId == -1 || bookPrice == -1)
+            return 0; // book data not stored
+
+        // // specify file name
+        const char *fileName = "books_data.dat";
+
+        // create an instance of ofstream for writing in a file
+        ofstream fout;
+
+        // // open file in binary mode for writing and append data
+        fout.open(fileName, ios::app | ios::binary);
+
+        // // check if the file is successfully opened
+        if (!fout.is_open())
+            return 0; // book data not stored
+
+        fout.write((char *)this, sizeof(*this));
+
+        return 1; // book data successfully stored
+    }
+};
+
+// // function to fetch books data from a fike and show
+void fetchAndShowEmployeeData()
+{
+    // // specify file name
+    const char *fileName = "books_data.dat";
+
+    // create an instance of ifstream for reading from a file
+    ifstream fin;
+
+    // // open file in binary mode for reading
+    fin.open(fileName, ios::in | ios::binary);
+
+    // // check if the file is successfully opened
+    if (!fin.is_open())
+    {
+        cout << "\nError: Unable to Open File...";
+        return;
+    }
+
+    // // create an instance of Employee to store fetched data
+    Employee tempEmployee;
+
+    fin.read((char *)&tempEmployee, sizeof(tempEmployee));
+
+    while (!fin.eof())
+    {
+        cout << endl;
+        tempEmployee.showEmployeeData();
+        cout << endl;
+        fin.read((char *)&tempEmployee, sizeof(tempEmployee));
+    }
+}
+
+// // function to search a book from file using book id
+void searchEmployeeById(int empId)
+{
+    // // specify file name
+    const char *fileName = "books_data.dat";
+
+    // create an instance of ifstream for reading from a file
+    ifstream fin;
+
+    // // open file in binary mode for reading
+    fin.open(fileName, ios::in | ios::binary);
+
+    // // check if the file is successfully opened
+    if (!fin.is_open())
+    {
+        cout << "\nError: Unable to Open File...";
+        return;
+    }
+
+    // // create an instance of Employee to store fetched data
+    Employee tempEmployee;
+    int found = 0;
+
+    fin.read((char *)&tempEmployee, sizeof(tempEmployee));
+
+    while (!fin.eof())
+    {
+        if (tempEmployee.getEmployeeId() == empId)
+        {
+            cout << "\n>>>>>>>>> Employee Found <<<<<<<<" << endl;
+            tempEmployee.showEmployeeData();
+            found = 1;
+            break;
+        }
+
+        fin.read((char *)&tempEmployee, sizeof(tempEmployee));
+    }
+
+    if (!found)
+        cout << "\nThere is No Employee Data Stored having Employee Id " << empId << endl;
+}
+
+// // Main Function Start
+int main()
+{
+    int n;
+
+    cout << "\nHow Many Employees' Data You Want to Store (MAX " << MAX_BOOKS << ") => ";
+    cin >> n;
+
+    // // invalid input
+    if (n < 1 || n > MAX_BOOKS)
+    {
+        cout << "\n!!! Invalid Input..." << endl;
+        return 0;
+    }
+
+    // // dynamically allocate memory for n objects of Employee
+    Employee *books = new Employee[n];
+
+    // // input, set and store books data
+    cout << "\n>>>>>>>>>> Enter Data of " << n << " Employees <<<<<<<<<<<<<" << endl;
+    for (int i = 0; i < n; i++)
+    {
+        cout << "\n>>>>>>>>>>> Enter Data of Employee " << i + 1 << " <<<<<<<<<<<<" << endl;
+
+        // // input and set book data
+        books[i].inputEmployeeData();
+
+        // // store book data
+        if (!(books[i].storeEmployeeData()))
+        {
+            cout << "\n!!! Employee Data Not Stored..." << endl;
+            return 0;
+        }
+    }
+
+    // // books data stored successfully
+    cout << "\nEmployees Data Successfully Stored..." << endl;
+
+    // // read and show books data
+    cout << "\n>>>>>>>>>> Employees Data Stored In File <<<<<<<<<<<<<<";
+    fetchAndShowEmployeeData();
+
+    // // get book id to search a book in file
+    int empId;
+
+    cout << "\nEnter Employee Id to Search A Employee => ";
+    cin >> empId;
+
+    // // search book
+    searchEmployeeById(empId);
+
+    cout << endl; // Add new line
+    cin.ignore();
+    return 0;
+}
+// // Main Function End