This document discusses control statements and loops in Visual Basic .NET (VB.NET). It covers conditional statements like If-Then, If-Then-Else, and If-Then-ElseIf. It also covers different types of loops in VB.NET including Do While, For Next, and For Each loops. Finally, it touches on VB.NET arrays, including how to declare, initialize, and use multidimensional and fixed size arrays.

1. Visual Programming .NET
By Dr. M. Sudharsan

2. VB.NET Control Statements
In VB.NET, the control statements are the
statements that controls the execution of the
program on the basis of the specified
condition. It is useful for determining whether
a condition is true or not. If the condition is
true, a single or block of statement is
executed. In the control statement, we will
use if- Then, if Then Else, if Then ElseIf and
the Select case statement.

4. • VB.NET provides the following conditional or
decision-making statements.
• If-Then Statement
• If-Then Else Statement
• If-Then ElseIf Statement

5. If-Then Statement
• The If-Then Statement is a control statement
that defines one or more conditions, and if the
particular condition is satisfied, it executes a
piece of information or statements.
If condition Then
[Statement or block of Statement]
End If

6. If (Boolean_expression) Then
'This statement will execute if the Boolean condi
tion is true
Else
'Optional statement will execute if the Boolean c
ondition is false
End I

8. If-Then-ElseIf statement
• The If-Then-ElseIf Statement provides a choice
to execute only one condition or statement
from multiple statements. Execution starts
from the top to bottom, and it checked for
each If condition

10. VB.NET Do Loop
• A Loop is used to repeat the same process
multiple times until it meets the specified
condition in a program. By using a loop in a
program, a programmer can repeat any
number of statements up to the desired
number of repetitions.

11. Types of Loops
• Do While Loop
• For Next Loop
• For Each Loop
• While End Loop

12. Do While Loop
• In VB.NET, Do While loop is used to execute
blocks of statements in the program, as long
as the condition remains true.
Do
[ Statements to be executed]
Loop While Boolean_expression

13. For Next Loop
• A For Next loop is used to repeatedly execute
a sequence of code or a block of code until a
given condition is satisfied. A For loop is useful
in such a case when we know how many times
a block of code has to be executed. In VB.NET,
the For loop is also known as For Next Loop.

14. For variable_name As [ DataType ] = start To end
[ Step step ]
[ Statements to be executed ]
Next

15. VB.NET For Each Loop
• In the VB.NET, For Each loop is used to iterate
block of statements in an array or collection
objects. Using For Each loop, we can easily
work with collection objects such as lists,
arrays, etc., to execute each element of an
array or in a collection.

16. For Each var_name As [ DataType ] In Collection
_Object
[ Statements to be executed]
Next

18. VB.NET Arrays
• An array is a linear data structure that is a
collection of data elements of the same type
stored on a contiguous memory location.
Each data item is called an element of the
array

19. Declaration of VB.NET Array
• We can declare an array by specifying the data
of the elements followed by parentheses () in
the VB.NET
Dim array_name As [Data_Type] ()

20. Initialization of VB.NET Array
• n VB.NET, we can initialize an array
with New keyword at the time of declaration.
For example,
Dim num As Integer() = New Integer(5) { }

21. Multidimensional Array
• In VB.NET, a multidimensional array is useful for
storing more than one dimension in a tabular
form, such as rows and columns. The
multidimensional array support two or three
dimensional in VB.NET.
Dim arr(5, 3) As Integer

22. Fixed Size Array
• In VB.NET, a fixed- size array is used to hold a
fixed number of elements in memory
Dim names( 0 to 4) As String
names(0) = "Robert"
names(1) = "Henry"
names(2) = "Rock"
names(3) = "James"
names(4) = "John"

23. VB.Net - Program Structure
• A VB.Net program basically consists of the
following parts −
• Namespace declaration
• A class or module
• One or more procedures
• Variables
• The Main procedure
• Statements & Expressions
• Comments

24. Imports System
Module Module1
'This program will display Hello World
Sub Main()
Console.WriteLine("Hello World")
Console.ReadKey()
End Sub
End Module