.net lab

Lab1/Lab1/Lab1/Lab1.cs

/// /// Program: Employee Sort /// /// Author: Nicholas J. Corkigian /// Date: February 2010 /// /// Purpose: This program reads the employee.txt data file and stores the information in an array of /// Employee objects. The user is then presented with a menu that allows them to select which /// of five fields to sort the resultant table by: Employee name, ID, rate, hours, or gross pay. /// /// The program ends when the user selects the exit option from the menu. /// using System; using System.IO; /// <summary> /// This is the main tester class that the program starts at /// </summary> class Lab1 { /// <summary> /// The main method reads the data file, populates the Employee array and provides a menu of sort options. /// </summary> /// <param name="args">Command line arguments are not used in this program</param> static void Main(string[] args) { int count; // Keep track of how many employees are instantiated bool loop = true; // A loop control variable string input; // The user's menu option pick as a string int choice; // The user's menu option pick as an integer Employee[] employees; // The array of Employee objects // Read the data file to build the Employee array and find out how many there are Read(out employees, out count); // Keep the menu loop running so the user can sort several times while (loop) { // Display the menu and retrieve the user's choice input = Menu(); // Based on the user's entry, sort using the appropriate option if (Int32.TryParse(input, out choice)) { switch (choice) { // Sort by employee name - ascending case 1: Sort(employees, count, 1); break; // Sort by employee ID number - ascending case 2: Sort(employees, count, 2); break; // Sort by hourly rate - descending case 3: Sort(employees, count, 3); break; // Sort by weekly hours - descending case 4: Sort(employees, count, 4); break; // Sort by gross pay - descending case 5: Sort(employees, count, 5); break; // Exit the program case 6: loop = false; break; // Trap invalid selections to try again default: Console.WriteLine("\n*** Invalid Choice - Try Again ***\n"); break; } // Display the table when a valid choice is made, otherwise display an error if (choice >= 0 && choice <= 5) DisplayTable(employees, count); } else Console.WriteLine("\n*** Invalid Choice - Try Again ***\n"); } } /// <summary> /// This method displays the entire table, including column headers /// </summary> /// <param name="employees">The array of employees</param> /// <param name="count">How many employees are in use</param> private static void DisplayTable(Employee[] employees, int count) { Console.Clear(); Console.WriteLine("Employee Number Rate Hours Gross Pay Nick's Company"); Console.WriteLine("==================== ====== ====== ===== ========= --------------"); // Display each employee in the array for (int i = 0; i < count; i++) employees[i].PrintEmployee(); Console.WriteLine(); } /// <summary> /// This method displays the menu options to the user and returns their selection /// </summary> /// <returns>The user's menu selection</returns> private static string Menu() { Console.WriteLine("1. Sort by Employee Name"); Console.WriteLine("2. Sort by Employee Number"); Console.WriteLine("3. Sort by Employee Pay Rate"); Console.WriteLine("4. Sort by Employee Hours"); Console.WriteLine("5. Sort by Employee Gross Pay"); Console.WriteLine("\n6. Exit"); Console.Write("\nEnter choice: "); return Console.ReadLine(); } /// <summary> /// This method reads the data file and stores all of the employee information in an array of Employees /// </summary> /// <param name="employees">The array of employees</param> /// <param name="count">How many employees are in use</param> private static void Read(out Employee[] employees, out int count) { count = 0; // The current number of employees string input; // One line of data read from the file employees = new Employee[100]; // The Employee array try { // Open the file for reading purposes FileStream file = new FileStream("employees.txt", FileMode.Open, FileAccess.Read); StreamReader reader = new StreamReader(file); // As long as there is data in the file, keep processing // Each employee record is comma separated, so explode each piece into an array, // create a new employee object and increment the count while ((input = reader.ReadLine()) != null) { string[] exploded = input.Split(','); employees[count] = new Employee(exploded[0], int.Parse(exploded[1]), decimal.Parse(exploded[2]), double.Parse(exploded[3])); count++; } reader.Close(); // Always good form to close the file } // Just in case the file can't be found - graceful exit catch (IOException e) { Console.WriteLine("*** File is empty - Program Aborting ***\n"); Environment.Exit(1); } } /// <summary> /// This method uses a Bubble Sort to rearrange the Employee array in order. Since there are /// five possible ways to sort, the outer loops remain the same and instead the condition is /// different for each field to sort on. /// </summary> /// <param name="emps">The array of employees</param> /// <param name="size">How many employees are in use</param> /// <param name="choice">The user selected sort choice</param> public static void Sort(Employee[] emps, int size, int choice) { for (int a = 0; a < size - 1; a++) for (int b = 0; b < size - 1; b++) switch (choice) { case 1: // Sort by employee name - ascending if (emps[b].GetName().CompareTo(emps[b + 1].GetName()) > 0) Swap(ref emps[b], ref emps[b + 1]); break; case 2: // Sort by employee ID - ascending if (emps[b].GetNumber() > emps[b + 1].GetNumber()) Swap(ref emps[b], ref emps[b + 1]); break; case 3: // Sort by hourly rate -descending if (emps[b].GetRate() < emps[b + 1].GetRate()) Swap(ref emps[b], ref emps[b + 1]); break; case 4: // Sort by weekly hours - descending if (emps[b].GetHours() < emps[b + 1].GetHours()) Swap(ref emps[b], ref emps[b + 1]); break; case 5: // Sort by gross pay - descending if (emps[b].GetGross() < emps[b + 1].GetGross()) Swap(ref emps[b], ref emps[b + 1]); break; } } /// <summary> /// This method is a utility method for the Bubble Sort. It just swaps two elements in the array /// </summary> /// <param name="a">First employee</param> /// <param name="b">Second employee</param> private static void Swap(ref Employee a, ref Employee b) { Employee temp; // A temporary holding spot for an employee temp = a; a = b; b = temp; } }