1 Microsoft® Visual Basic®.NET Language # 2

2 Flow-Control Statements If … End If Select Case … End Select For… Next Do … Loop Exit

3 If … End If If {Condition} Then … End If If {Condition} Then … Else … End If If {Condition1} Then … ElseIf {Condition2} Then … End If Example: If Score>80 Then Result = "A" ElseIf Score>50 Then Result = "B" Else Result = "F" End If

4 Select Case … End Select Select Case {Expression} Case {value1} … Case {value2} …. Case Else … End Select Example : Select Case Score Case 80 To 100 Result = "A" Case 70 To 79 Result = "B" Case 60 To 69 Result = "C" Case Else Result = "F" End Select

5 Example : Select…Case Select Case Score Case 80 To 100 Result = "A" Case 70 To 79 Result = "B" Case 60 To 69 Result = "C" Case Else Result = "F" End Select Example: If…Then…Else, Select…Case Example: If…Then…Case If Score>80 Then Result = "A" ElseIf Score>50 Then Result = "B" Else Result = "F" End If

6 Example 1:

7 For… Next For {Counter} = {Start} To {End} … Next ‘ or For {Counter} As Integer = {Start} To {End} … Next Example1 : Dim Result As Integer = 0 Dim I As Integer For I = 1 To 5 Result += I Next MsgBox (Result & I) Example2 : Dim Result As Integer = 0 For I As Integer = 1 To 5 Result += I Next MsgBox (Result & I)

8 Do … Loop Do {While/Until} {Condition} … Loop Example1 : Dim Result As Integer = 0 Dim I As Integer = 0 Do Until I>2 I += 1 Result += I Loop MsgBox (Result & I) Do … Loop {While/Until} {Condition} Example2 : Dim Result As Integer = 0 Dim I As Integer = 0 Do While I < 2 I += 1 Result += I Loop MsgBox (Result & I)

9 Exit Exit from block of statements in a control structure. Example : Dim I As Integer = 0 Dim Result As Integer = 0 Do Until I>4 I += 1 Result += I If Result>5 Then Exit Do End If Loop MessageBox.Show (Result & I)

10 Sub {Scope} Sub {name}({param1}…) End Sub Public Sub SayHello(ByVal Name As String) MessageBox.Show ("Hello " + Name) End Sub Public Sub SayHello() MessageBox.Show ("Hello World") End Sub Call SayHello("Peter")

11 Function {Scope} Function {name}({param1}…) As {Type} End Sub Public Function Add(ByVal Val1 As Integer, ByVal Val2 As Integer) As Integer Return Val1+Val2 End Sub A = Add( 3, 4 ) Public Function Add() As Integer Return 0 End Sub