IN COLLABORATION WITH IVTB. Diploma in Information Technology. Examinations for / Semester 2

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1 IN COLLABORATION WITH IVTB Diploma in Information Technology DIP/03/Full Time Examinations for / Semester 2 MODULE: VISUAL PROGRAMMING MODULE CODE: BISE070 Duration: 2 Hours + 10 Minutes (Reading Time) Instructions to Candidates: 1. Answer all questions. 2. Questions may be answered in any order but your answers must show the question number clearly. Always start a new question on a fresh page. 3. All questions do not carry equal marks. 4. Total Marks: 100. This question paper contains 4 questions and 8 pages. Page 1 of 8

2 QUESTION 1: (23 MARKS) ANSWER ALL QUESTIONS (a) Explain the.net Framework. Support your answer with a diagram (b) Outline three differences between VB.net and the previous VB versions. (5 Marks) (3 Marks) (c) Write a VB.Net program to display the square of the number from 10 to 15 in a message box. (3 Marks) (d) Cobalt 60, a radioactive element used in cancer therapy, decays over a period of time. Each year 12% of the amount present at the beginning of the year will be decayed. Write a VB.NET program to determine the amount of this element remaining after 8 years. Assume that you input amount and years in textboxes txtamount and txtyear respectively. Display your result in list box, lstdecay as shown below. You should format your output with appropriate zones. (8 Marks) Page 2 of 8

3 (e) Use With statement to set the properties of a textbox to : I. Read-only II. Background color to blue (4 Marks) QUESTION 2: (27 MARKS) (a) The program below calculates the area of a circle. Write the function definition for Calculateareafromradius. (5 marks) Private Sub cmdarea_click( ) Handles cmdarea.click Dim area As Double area = Calculateareafromradius(10) MessageBox.Show(area, "area") (b) Predict the values of the variable count at lines A, B, C, D, E and F. (6 marks) Public Class frmmain Private Count As Integer=3 Private Sub btncalculate_click( ) Dim Count As Integer = 4 Alter(Count) Count = Count + 1 line A Private Sub btnclear_click( ) Dim Count As Integer =7 Count = Count + 1 Line B Page 3 of 8

4 Private Sub btnvalid_click( ) Count = Count + 1 Line C Change(count) Private Sub btnexit_click( ) Count = Count + 1 Line D Private Sub Alter (ByVal countx as Integer) Counter += 2; Line E Private Sub Alter (ByRef countx as Integer) Counter += 2; Line F End Class (c) Write VB.NET codes that use two separate input boxes to ask the user for a first and last name, and then display in a message box the total number of letters in both names. (3 marks) (d) Write VB.NET codes when the buttons shown below are clicked. (8 marks) Command Button Add Item is used to add an item in the list box, using an input box. Command Button Del Item is used to delete a selected Item from the list box Command Button Clear - is used to clear the listbox Command Button Item Count is used to count the number of items in the listbox and displays the result in a message box. Page 4 of 8

5 (e) Write codes for the command button Display such that if the textbox is empty, a valid error message is displayed. If an invalid date is input a message box is displayed informing the user that the data entered is not valid. (5 marks) QUESTION 3: (25 MARKS) (a) The first step in designing a human computer interface involves Knowing the user. As a designer, state five issues you need to know about a user. (5 Marks) Page 5 of 8

6 (b) Identify five ways of improving this menu. (5 Marks) Query List of customer supplier list purchase list by date purchase list by supplier Payment Member Payment Supplier (c) Make use of a For Each Next statement to reset the textbox, radio buttons, checkboxes to empty in the following form, when the Reset button is clicked (6 Marks) (d) Rewrite the program below using a Select Case Statement. If txtcustomer.text = Darren Then Messagebox.show( Your Favorite Color is Yellow ) Elseif txtcustomer.text = Stephanie Then Messagebox.show( Your Favorite Color is Red ) Elseif txtcustomer.text = Cathy Then Messagebox.show( Your Favorite Color is Green ) Elseif txtcustomer.text = Zoe Then Page 6 of 8

7 Messagebox.show( Your Favorite Color is Purple ) Elseif txtcustomer.text = Edward Then Messagebox.show( Your Favorite Color is Blue ) End If (4 Marks) (e) Explain the codes in the Try - End Try block. (5 Marks) Private Sub cmdmultipleerror_click( ) Handles cmdmultipleerror.click Try pic1.image = Image.FromFile("A:\compu.gif") Catch When Err.Number = 53 MessageBox.Show("The file does not exist!", CStr(Err.Number) + ": " + Err.Description, MessageBoxButtons.OK, MessageBoxIcon.Error) Catch When Err.Number = 7 MessageBox.Show("Is this really a Gif file?", Err.Description, MessageBoxButtons.OK, MessageBoxIcon.Error) Catch MessageBox.Show("Problem loading file!", Err.Description, MessageBoxButtons.OK, MessageBoxIcon.Error) Finally MessageBox.Show("Error handler complete!", "Error Information", MessageBoxButtons.OK, MessageBoxIcon.Information) End Try Page 7 of 8

8 QUESTION 4: (25 MARKS) (a) Define Dataset. Outline its importance in ADO.NET. Support your answer with a suitable example. (8 Marks) (b) The job details table and Employee Details form shown below has been designed using MS Access and VB.NET respectively. Write the codes for the command button populate so that when the user clicks on it, all the Job_Type records are displayed in the combobox cbojobtype. (Path of the database: c:\project\employee.mdb) (10 Marks) (c) Using VB.NET write appropriate codes to: (i) Create the file subject.txt on the C drive, with the following details: Chemistry, Physics, Biology, Economics. (ii) Display the content of the file subject.txt in a listbox. (7 Marks) ***END OF QUESTION PAPER*** Page 8 of 8