This document discusses three types of decision making statements in VB.NET: If...Then, If...Then...Else, and Select Case. If...Then statements execute code if a condition is true, If...Then...Else statements execute one block of code if true and another if false, and Select Case statements choose between multiple blocks based on a variable's value. Examples are provided for each type of statement.

2. Introduction
• Decision making statements in VB.NET are used to
control the flow of a program by checking one or more
conditions. There are 3 types, They are
– If … then
– If …. Then … else
– Select case

3. If .. then
• This statement is used to test a condition and execute
a set of statements if the condition is true . If it is
false, the statement which is next to the if … then
structure is executed.

4. syntax
If Condition Then
One or more Visual Basic statements
End If

5. Example
Dim mark as integer
If mark>40 then
Msgbox (“Pass”)
End if

6. If … then … else
• This statement is used to test a condition and
execute a set of statements if the condition is
true and execute another set of statement if it is
false.

7. Syntax
If condition Then
One or more statements
Else
One or more statements
End If

8. Example
• Dim a As Integer
Dim b As Integer
a = 3
b = 4
If a > b Then
MsgBox ("a is greater then b")
Else
MsgBox ("b is greater then a")
End If

9. Select case statement
• The Select Case statement executes one of several
groups of statements depending on the value of an
expression. If your code has the capability to handle
different values of a particular variable then you can
use a Select Case statement. You use Select Case to test
an expression, determine which of the given cases it
matches and execute the code in that matched case.

10. Syntax
• Select Case expression
Case value1
Statement 1
Case value2
Statement 2
Case value3
Statement 3
Case value4
.
.
.
Case Else
Statement
End Select

11. Example
• ' Examination Grades
Dim grade As String
Private Sub Compute_Click( )
grade= txtgrade.Text
Select Case grade
Case "A"
result.Caption="High Distinction"
Case "A-"
result.Caption="Distinction"
Case "B"
result.Caption="Credit"
Case "C"
result.Caption="Pass"
Case Else
result.Caption="Fail"
End Select
End Sub

24. Arrays