VB.Net Tutorial/Statements/While

Combine While and If to search in an array

Imports System
Public Class WhileExample
    Shared Sub Main()
        Dim iCounter As Integer = 0
        Dim arrList(9) As String
        Dim iMatch As Integer = -1
        Dim sMatch As String
        sMatch = "A"
        arrList(0) = "A"
        arrList(1) = "B"
        arrList(2) = "C"
        arrList(3) = "D"
        arrList(4) = "E"
        arrList(5) = "G"
        arrList(6) = "H"
        arrList(7) = "I"
        arrList(8) = "J"
        arrList(9) = "K"
        While iCounter <= 9 AND iMatch = -1
            If arrList(iCounter) Like sMatch Then
                iMatch = iCounter
            Else
                iCounter = iCounter + 1
            End If
        End While
        If iMatch <> -1 Then
            System.Console.WriteLine("Matched " & iMatch)
        End If
    End Sub
End Class

Matched 0

Draw square of * by using nested while loop

Module Tester
   Sub Main()
      Dim side As Integer    
      Dim row As Integer = 1 
      Dim column As Integer  
      side = 12
      If side <= 20 Then 
         While row <= side 
            column = 1
            While column <= side
               Console.Write("* ") 
               column += 1         
            End While
            Console.WriteLine() 
            row += 1            
         End While
      Else 
         Console.WriteLine("Side too large")
      End If
   End Sub
End Module

* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * *

Using counter-controlled repetition

Module modAverage
    Sub Main()
        Dim total As Integer         
        Dim gradeCounter As Integer  
        Dim grade As Integer         
        Dim average As Double        
        total = 0                    
        gradeCounter = 1             
        While gradeCounter <= 10
            grade = 12
            total += grade    
            gradeCounter += 1 
        End While
        average = total / 10
        Console.WriteLine("Class average is {0}", average)
    End Sub 
End Module

Class average is 12

While structure

Module Tester
    Sub Main()
        Dim product As Integer = 2

        While product <= 1000
            Console.Write("{0}  ", product)
            product = product * 2
        End While
        Console.WriteLine("Smallest power of 2 " & _
           "greater than 1000 is {0}", product)
    End Sub " Main
End Module

2  4  8  16  32  64  128  256  512  Smallest power of 2 greater than 1000 is 1024