A) In VB.Net, what is the method that is available without creating the instance of the class
· 1. Instance method
· 2. overloading method
· 3. Shared method
· 4. class methods
Ans: ?
3
??
B) In VB.Net, what is finalise method and what are the role of it?
·
1. Release object memory
· 2. Release memory
· 3. it calls when page is closed
Ans: ??
1
?
C) In VB.Net, passing an array using ByRef or ByVal makes a difference if you use a ReDim statement inside the called procedure.? Which array size will be affected ?
· 1. an array passed by ByVal
· 2. an array passed by ByRef
· 3. both affected
· 4. none affected
Ans: ???
3
D) In VB.Net, ParamArray arguments are passed by in a function?
·
1. Always by value
· 2. Always by reference
· 3. both
· 4. none
Ans: ?
2
??
E) How are parameters referenced by default in VB.Net?
· 1. ByObject
· 2. ByVal
· 3. ByRef
· 4. None
Ans: ??
2
?
F) Does ISDBNull() exsist in VB.Net?
Select Answer:
·
1. True
?????
?????? 2. False
Ans: ?
1
??
G) In VB.Net, constructor is always
·
1. sub new()
· 2. constructor()
· 3. base class()
· 4. the class name itself
Ans: ??
1
?
H) In VB.NET, what is used to join strings
·
1. Plus sign
· 2. Ampersand
· 3. both
Ans: ??
3
?
?
I) In Java, which statements ARE true?
1.??????
When a thread sleeps, its locks are released
2.??????
If a class has synchronized code, multiple threads can still access the non synchronized code.
3.??????
Methods and variables can be protected from concurrent access problems by marking them with the synchronized keyword.
4.??????
When a thread invokes wait(), its locks are released.
5.??????
A static method cannot be synchronized
Ans: ???
2
?
J) Which TWO combinations below consist (and only) the necessary classes in package java.io to read a single line of Traditional Chinese text via TCP connections?
? I. Socket
? II. TCPSocket
? III. PipedInputStream
? IV. BufferedInputStream
? V. BufferedReader
? VI. InputStreamReader
? VII. LineNumberReader
? VIII. StringReader
?
1.??????
(I) + (III) + (VI) + (VII)
2.??????
(I) + (IV) + (VI) + (V)
3.??????
(II) + (VI) + (VII)
4.??????
(I) + (IV) + (VI) + (VII)
5.??????
(I) + (VI) + (VIII)
Ans: ??
2
?
?
Question 1
?
The VB function, GetCurrencyCode demonstrates the translation between the currency code and currency number. ?However, the performance of this function is not good enough; the higher order of input number takes much more times to calculate. ?Please suggest a way to improve the program performance:
?
Function GetCurrencyCode(ByVal input As String) As String
If input = "01" Then
return = "AFA"
ElseIf input = "02" Then
return = "ALL"
ElseIf input = "03" Then
return = "DZD"
ElseIf input = "04" Then
return = "USD"
ElseIf input = "05" Then
return = "HKD"
ElseIf input = "75" Then
return = "EUR"
ElseIf input = "76" Then
return = "XCD"
ElseIf input = "77" Then
return = "AMD"
End If
End Function
?
Answer:
?
Question 2
?
Write a function that reverses the order of the words in a string. For instance, your function should transform the string “Do or do not, there is no try.” To “try. No is there not, do or Do”. Assume that all words are space delimited and treat punctuation the same as letters.
?
Use your most hands-on programming language.
?
Answer:
?
Question 3
?
Study the following VB program:
?
Imports
System
Imports
System.IO
Module
Module1
Public
ArtList As ArrayList
End
Module
?
Public
Class Form1
Inherits
System.Windows.Forms.Form
?
#Region " Windows Form Designer generated code "
…
#EndRegion
?
<[Serializable]()> PublicClass Art
Public
Title AsString
Public
Des AsString
Public
Value AsInteger
Public
Price AsDouble
Public
Picture AsString
End
Class
?
Private
Sub Button1_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim
myArt AsNewObject
Dim
hashtable AsNew Collections.Hashtable
Dim
key AsString
?
Try
myArt = New Art
With
myArt
.Title = "Title"
.Des = "Desc"
.Value = 123
.Price = 321.05
End
With
key = myArt.Title & myArt.Des & CStr(myArt.Value) & CStr(myArt.Price)
hashtable.Add(key, myArt)
ArtList.Add(myArt)
?
Catch
ex As Exception 'This is the line 94’
MsgBox(ex.Message & vbCrLf & ex.StackTrace)
End
Try
End
Sub
End
Class
A form is created on which a button control is placed. ?When the Button1_Click is fired, a message box is popup:
?（圖片未上傳）
?
What is the problem and how to fix it?
?
Answer:
?
Question 4
?
In the following VB program, please states any potential problem(s) and how to correct.
?
Private Sub btnCalc_Click( )
Dim result As Integer
Try
Me.Cursor = Windows.Forms.Cursors.WaitCursor
result = Convert.ToInt32(txtInput1.Text) / Convert.ToInt32(txtInput2.Text)
txtResult.Text = result
Me.Cursor = Windows.Forms.Cursors.Default
Catch ex As Exception
MsgBox(ex.StackTrace)
Catch ex As ArgumentNullException
MsgBox("Input Test box cannot be null.")
Catch ex As OverflowException
MsgBox("Input Test box 2 cannot be zero!")
Catch ex As FormatException
MsgBox("Input Test box should be numeric format!")
End Try
End Sub
?
Answer:
?
Question 5
?
GetRecordset() is a VB function that returns a ADODB.Recordset object:
?
|
??????
|
Ref_ID
|
Qty
|
Price
|
|
Row 0
|
00123
|
1000
|
60.50
|
|
Row 1
|
00123
|
2000
|
60.00
|
|
Row 2
|
00123
|
3500
|
59.50
|
|
Row 3
|
00124
|
3000
|
60.50
|
|
Row 4
|
00125
|
2000
|
59.50
|
|
Row 5
|
00125
|
1000
|
58.00
|
?
?(This recordset is sorted by Ref_ID)
?
The following program
?
Dim rst as ADODB.Recordset
Rst = GetRecordset
Do While Not rst.EOF
Console.writeline(rst.Fields("Ref_ID") & vbcrlf & rst.Fields("
Qty
") & vbcrlf & rst.Fields("
Price
"))
rst.MoveNext()
Loop
?
Can generate the following output:
?
Output:
?
00123 1000 60.50
00123 2000 60.00
00123 3500 59.50
00124 3000 60.50
00125 2000 59.50
00125 1000 58.00
?
Please suggest how to modify the above program to generate the following output:
?
Output:
00123
1000 ?? ?????? 60.50
2000 ?? ?????? 60.00
3500??????????? 59.50
---- ??????????? -----
6500??????????? 60.00
00124
3000??????????? 60.50
---- ??????????? -----
3000 ?? ?????? 60.50
00125
2000???? ?????? 59.50
1000???? ?????? 58.00
---- ??????????? -----
3000???? ?????? 58.75
?
?
Answer:
?
Question 6
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Problem: Use your most hands-on programming language to implement a function that prints all possible combinations of the characters in a string. These combinations range in length from one to the length of the string. Two combinations that differ only in ordering of the characters ARE the same combination.? In other words, “12” and “31” are different combinations from the input string “123”, but “21 is the same as “12”.
?
For example, if we use “wxyz” as parameter for Combination(“wxyz”) the function will print out
?
w
x
y
z
wx
wy
wz
xy
xz
yz
wxy
wxz
wyz
xyz
wxyz
?
Answer:
?
Question 7
?
Module modFree
#Region "clsShape"
Public Class clsShape
Private m_Area As Double
Private m_Sides As Integer
?
Public Sub New()
m_Area = 0.0
m_Sides = 0
End Sub
?
Public Sub New(ByVal Sides As Integer)
m_Sides = Sides
End Sub
?
Public Sub New(ByVal Area As Double)
m_Area = Area
End Sub
?
Public Sub New(ByVal Area As Double, ByVal Sides As Integer)
m_Area = Area
m_Sides = Sides
End Sub
?
Public Property Area() As Double
Get
Return m_Area
End Get
Set(ByVal Value As Double)
m_Area = Value
End Set
End Property
?
Public Property Sides() As Integer
Get
Return m_Sides
End Get
Set(ByVal Value As Integer)
m_Sides = Value
End Set
End Property
End Class
#End Region
?
?
#Region "clsTriangle"
Public Class clsTriangle
Inherits clsShape
?
Public Sub New()
MyBase.New(3)
End Sub
?
Public Sub New(ByVal Area As Double)
MyBase.New(Area, 3)
End Sub
?
Public Function CalculateArea(ByVal SideBase As Double, ByVal Height As Double, _ Optional ByVal AssignToArea As Boolean = False) As Double
Dim Area As Double = (SideBase * Height) / 2
?
If AssignToArea Then
Me.Area = Area
End If
?
Return Area
End Function
End Class
#End Region
?
Public Sub Main()
Dim objTriangle As New clsTriangle
Dim objShape As New clsShape
?
objTriangle.Area = -330
objTriangle.Sides = 5.5
objTriangle.CalculateArea(10.0, 2.5)
?
objShape.Area = 123
objShape.Sides = -2
objShape = CType(objShape, clsTriangle)
?
Console.WriteLine(TypeOf objTriangle Is clsShape)
Console.WriteLine(TypeOf objShape Is clsTriangle)
Console.WriteLine(objTriangle.Area)
End Sub
End Module
?
7.1 Please find the line of code from the procedure Main to cause run-time error.
?
Answer:
?
7.2 Please write the result output from the procedure Main.
?
Answer:
?
Question 8
?
Consider the following account and customer tables:
?
|
cust_tbl
|
|
cust_id
|
title
|
e_first_name
|
e_last_name
|
address1
|
.
|
|
0
|
MR
|
Martin
|
Ma
|
.
|
?
|
|
1
|
MR
|
Kirs
|
Cheung
|
.
|
?
|
|
2
|
MR
|
Ricky
|
Chan
|
.
|
?
|
|
3
|
MR
|
Tom
|
Kwan
|
.
|
?
|
|
4
|
MR
|
Corporate Default
|
Corporate Default
|
.
|
?
|
|
5
|
MRS
|
Mary
|
Mok
|
.
|
?
|
|
.
|
.
|
.
|
.
|
.
|
?
|
?
|
acc_grp_cust_tbl
|
|
acc_group
|
Cust_id1
|
Cust_id2
|
Cust_id3
|
Cust_id4
|
|
1400
|
0
|
1
|
2
|
?
|
|
1500
|
3
|
4
|
?
|
?
|
|
1600
|
5
|
?
|
?
|
?
|
|
.
|
.
|
.
|
.
|
.
|
|
.
|
.
|
.
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.
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.
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?
The acc_grp_cust_tbl table is responsible to store the customer ID, and the cust_tbl table is responsible to store customer personal information such as name, address, etc… Please write a SQL query in order to provide following result.
?
|
ACC_GROUP
|
PAYEENAMES
|
|
1400
|
Ma Martin/Cheung Kris/Chan Ricky
|
|
1500
|
Kwan Tom/Corporate Default Corporate Default
|
|
1600
|
Mok Mary
|
|
.
|
.
|
|
.
|
.
|
?
Answer:
?