UNIVERSITY OF THE FREE STATE MAIN & QWA-QWA CAMPUS RIS 124 DEPARTMENT: COMPUTER SCIENCE AND INFORMATICS CONTACT NUMBER:

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1 UNIVERSITY OF THE FREE STATE MAIN & QWA-QWA CAMPUS RIS 124 DEPARTMENT: COMPUTER SCIENCE AND INFORMATICS CONTACT NUMBER: EXAMINATION: Main End-of-year Examination 2013 PAPER 1 ASSESSORS: Prof. P.J. Blignaut & Mr. F. Radebe MODERATOR: Dr. L. de Wet TIME: 4 hours MARKS: 170 (+ 4 bonus marks) Answer the following questions by developing the solutions in C#. Make sure that you enter your name, student number and question number for every class in a comment block at the top of the code window. You will not get marks if you do it, but you will lose 3 marks for every question if you don t do it. You might even get zero for the entire test if you don t do it! Make sure that you give appropriate names to all controls and variables. Create the following folder on the T-drive in the format Studentnumber_Surname, e.g _Blignaut This is an open-book test. You may use the text book Be Sharp with C# but no other sources, written or electronic, will be allowed. Question 1 Consider the following character string: "John Michel is sick, and his teacher, Margaret Green, sends his sister, Nancy Michel, to find some medicine from doctor Hubert Ashton." 1.1 Develop a console application to replace all occurrences of "Michel" with "Black", "Green" with "Brown" and "Ashton" with "White". Your program must be generic in the sense that a user must be able to enter any sentence and ask for replacement of any word(s) with other(s). Note that there may be any number of words to be replaced. 1.2 Display the total number of replacements. For the example above, there are 4 replacements. [20]

2 2 Question 2 You will be provided with a tab-separated text file with the minimum and maximum temperatures of each day of January. Write a console application to display the smallest minimum temperature along with the day on which it occurred as in the example. Hint: The hex value for in the UTF table is B0. [20] Question 3 You will be provided with an Access database, Plants.accdb, with the common names and scientific names of plants. Write a console application that will allow the user to enter a common name or any part thereof and then display the common names and scientific names in two columns as in the example. The user must be allowed to enter more plant names if he/she wants. [20] Question 4 Consider the scenario of a physician s diary. There are two types of appointments, namely consultations and operations. 4.1 Develop the classes Develop an abstract class CAppointment. (12) - Make provision for read-only properties for the date and time of the appointment and the name of the patient. - The constructor must initialise the above-mentioned properties. - Add an abstract method, Details(), that will return a string with all details of the appointment Develop a class COperation that is a CAppointment. (13) - Add a read-only property for the procedure to be done. A typical procedure would be Remove appendix or Remove tonsils. - The constructor must assign the above-mentioned property. - Override the Details method of the base class with a method that returns a string with all details of the appointment: Date/Time, Patient and Procedure. Normally, there would have been other sub-classes as well, but for the purposes of the examination you don t have to develop them.

3 4.2 Implement the class structure in a Windows Forms application as in the screen print below The form has a list box, property grid and five buttons. (4) Write the code for the Close button. (1) Disable the New consultation button since you are not going to implement it for this examination. (1) Declare a generic list of CAppointment, lstappointments, as a private data member of the form. Instantiate this list in the form s constructor. Remember to add the necessary namespaces to the application. (4) Develop a new form that will be used as a dialog box to enter a new operation to the diary. See the example below. - Add a DateTimePicker and two text boxes for the data and time of the operation, the patient name and the procedure to be executed to the form. Make sure that you give appropriate names to all controls. (3) - Add two buttons to the form to close it with the appropriate DialogResult property. (2) Add read-only properties for the date and time of the operation, the patient name and procedure to the class of the form in (6) Write a public ShowDialog() method for the form in This method should have no parameters and must return a DialogResult value based on the button that was clicked. Call the base.showdialog() method and then assign the values of the respective controls to the appropriate properties (question 4.2.6) prior to return. (8)

4 Write the code for the New Operation button in the main form. When the user clicks the button, the dialog box of question should appear to allow the user to enter the date and time of the operation as well as the name of the patient and the procedure to be executed. Add the new appointment to lstappointments. Add the date and time of the operation to the list box. (9) Write code for the SelectedIndexChanged() event handler of the list box to display all properties of the selected object in the property grid. Note that the property grid will display all properties but only allow edits for properties that are public. (3) Hint: Use the SelectedObject property of the property grid Write a method, SaveAppointments(), to serialize the entire list of appointments to a file Appointments.bin. Call this method from the FormClosing() event handler. (11) Write a method, LoadAppointments(), to deserialize the contents of the file Appointments.bin and put the contents in lstappointments. You should also add the date and time of each appointment in the list to the list box. Call this method from the FormLoad() event handler. (13) Write the code to delete an appointment. Note that the appointment must be removed from the generic list of appointments as well as the list box. Make provision for all possible errors. (6) Write code for the double click event handler of the list box. A message box should be displayed with details about the selected appointment. (4) Write the code for the List button. When the user clicks the button, all appointments (operations and others) with complete details must be displayed in order of date and time. (14) [114]

5 5 MEMORANDUM Question 1 class Program static void Main(string[] args) Console.Write("Original sentence: "); string s = Console.ReadLine(); //string s = "John Michel is sick, and his teacher, Margaret Green, sends his sister, Nancy Michel, to find some medicine from doctor Hubert Ashton."; int n = 0; do Console.Write("String to be replaced: "); string stobereplaced = Console.ReadLine(); Console.Write("String to replace with: "); string sreplacewith = Console.ReadLine(); s = s.replace(stobereplaced, sreplacewith); Console.Write("Another one (Y/N)?... "); string[] Parts = s.split(new string[] sreplacewith, StringSplitOptions.None); n += Parts.Length - 1; while (Console.ReadLine().ToUpper() == "Y"); Console.WriteLine(s); Console.Write("Replacements: " + n.tostring()); Console.Write("\n\nPress any key to exit..."); Console.ReadKey(); //Main

6 6 Question 2 class Program static void Main(string[] args) string[] Days = new string[0]; int[] mintemperatures = new int[0]; int n = 0; using (StreamReader f = new StreamReader("Temperatures.txt")) while (!f.endofstream) n++; string[] Data = f.readline().split('\t'); Array.Resize(ref Days, n); Array.Resize(ref mintemperatures, n); Days[n - 1] = Data[0]; try mintemperatures[n - 1] = int.parse(data[1]); catch int mintemperature = mintemperatures.min(); string minday = Days[minTemperatures.ToList().IndexOf(minTemperature)]; Console.WriteLine("Minimum temperature : " + mintemperature + (char)176 + "C on " + minday); Console.Write("\n\nPress any key to exit..."); Console.ReadKey();

7 7 Question 3 class Program static void Main(string[] args) //Connection string sconnectionstring = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=Plants.accdb"; OleDbConnection cnplants = new OleDbConnection(sConnectionString); cnplants.open(); bool isanotherone = true; do //User input Console.Clear(); Console.Write("Common name: "); string scommon = Console.ReadLine(); //SQL SELECT string sql = "SELECT CommonName, ScientificName " + "FROM Plants " + "WHERE CommonName LIKE '%" + scommon + "%' " + "ORDER BY CommonName, ScientificName"; //List matches OleDbCommand cmd = new OleDbCommand(sql, cnplants); OleDbDataReader reader = cmd.executereader(); while (reader.read()) Console.WriteLine(reader[0].ToString() + "\t" + reader[1].tostring()); reader.close(); //Another one? Console.Write("\nAnother one ('Y/N')? "); isanotherone = char.toupper(console.readkey().keychar) == 'Y'; while (isanotherone); //Main //class Program

8 8 Question public abstract class CAppointment public DateTime DateTime get; private set; public string Patient get; private set; public CAppointment(DateTime _DateTime, string _Patient) DateTime = _DateTime; Patient = _Patient; //Constructor public abstract string Details(); //class CAppointment public class COperation : Cappointment public string Procedure get; private set; public COperation(DateTime _DateTime, string _Patient, string _Procedure) : base(_datetime, _Patient) Procedure = _Procedure; public override string Details() return "Date/Time: " + this.datetime.tostring("dd MMMM yyyy HH:mm") + "\n" + "Patient: " + this.patient + "\n" + "Procedure: " + this.procedure; //class COperation Form name Control names private void btnclose_click(object sender, EventArgs e) this.close(); btnnewconsultation.enabled = false; using System.Collections.Generic; public partial class CfrmAppointments : Form private List<CAppointment> lstappointments; public CfrmAppointments() InitializeComponent(); lstappointments = new List<CAppointment>(); DateTimePicker, 2 text boxes, properly named Two buttons, properly named with DialogResult properties

9 public DateTime dtoperation get; private set; public string PatientName get; private set; public string Procedure get; private set; public override DialogResult ShowDialog() base.showdialog(); dtoperation = datetimepicker.value; PatientName = txtpatient.text; Procedure = txtprocedure.text; return this.dialogresult; private void btnnewoperation_click(object sender, EventArgs e) CfrmNewOperation frmoperation = new CfrmNewOperation(); if (frmoperation.showdialog() == System.Windows.Forms.DialogResult.OK) COperation Operation = new COperation(frmOperation.dtOperation, frmoperation.patientname, frmoperation.procedure); lstappointments.add(operation); lstbxappointments.items.add(operation.datetime.tostring("dd/mm/yyyy HH:mm")); //btnnewoperation_click private void lstbxappointments_selectedindexchanged(object sender, EventArgs e) int i = lstbxappointments.selectedindex; if (i >= 0) propertygrid.selectedobject = lstappointments[i]; [Serializable] in COperation and Cappointment using System.Runtime.Serialization; using System.Runtime.Serialization.Formatters.Binary; private void CfrmAppointments_FormClosing(object sender, FormClosingEventArgs e) SaveAppointments(); private void SaveAppointments() using (FileStream strm = new FileStream("Appointments.bin", FileMode.Create)) IFormatter formatter = new BinaryFormatter(); formatter.serialize(strm, lstappointments); //SaveAll

10 private void CfrmAppointments_Load(object sender, EventArgs e) LoadAppointments(); private void LoadAppointments() using (FileStream strm = new FileStream("Appointments.bin", FileMode.Open)) IFormatter formatter = new BinaryFormatter(); lstappointments = (List<CAppointment>)formatter.Deserialize(strm); foreach (CAppointment appointment in lstappointments) lstbxappointments.items.add(appointment.datetime.tostring("dd/mm/yyyy HH:mm")); //LoadAppointments private void btndeleteappointment_click(object sender, EventArgs e) int i = lstbxappointments.selectedindex; if (i >= 0) lstbxappointments.items.removeat(i); lstappointments.removeat(i); if (lstbxappointments.items.count > 0) lstbxappointments.selectedindex = 0; private void lstbxappointments_doubleclick(object sender, EventArgs e) int i = lstbxappointments.selectedindex; if (i >= 0) MessageBox.Show(lstAppointments[i].Details(), "Appointment details"); private void btnlistappointments_click(object sender, EventArgs e) string s = "Time\t" + "Patient".PadRight(20) + "\n" + "====\t" + "".PadRight(20, '=') + "\n"; lstappointments = lstappointments.orderby(app => app.datetime).tolist(); foreach (CAppointment appointment in lstappointments) s += appointment.datetime.tostring("hh:mm") + "\t" + appointment.patient.padright(20); if (appointment is COperation) s += ((COperation)appointment).Procedure + "\n"; MessageBox.Show(s);