VB.NET-INFORMATIONS.COM



VB.NET Program Flow Control Tutorials

How to use FOR NEXT loop in vb.net

How to use FOR NEXT loop in vb.net

Whenever you face a situation in programming to repeat a task for several times (more than one times ) or you have to repeat a task till you reach a condtition, in these situations you can use loop statements to achieve your desired results.

FOR NEXT Loop, FOR EACH Loop , WHILE Loop and DO WHILE Loop are the Commonly used loops in Visual Basic.NET 2005 ( VB.NET 2005) .

FOR NEXT Loop :

The FOR NEXT Loop , execute the loop body (the source code within For ..Next code block) to a fixed number of times.

  
For var=[startValue] To [endValue] [Step]
   [loopBody]
Next [var]

var : The counter for the loop to repeat the steps.

starValue : The starting value assign to counter variable .

endValue : When the counter variable reach end value the Loop will stop .

loopBody : The source code between loop body

Lets take a simple real time example , If you want to show a messagebox 5 times and each time you want to see how many times the message box shows.

  
1.	startVal=1
2.	endVal = 5
3.	For var = startVal To endVal
4.	    show message
5.	Next var

Line 1: Loop starts value from 1

Line 2: Loop will end when it reach 5

Line 3: Assign the starting value to var and inform to stop when the var reach endVal

Line 4: Execute the loop body

Line 5: Taking next step , if the counter not reach the endVal

VB.NET Source Code

  
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object,
	ByVal e As System.EventArgs) Handles Button1.Click
        Dim var As Integer
        Dim startVal As Integer
        Dim endVal As Integer
        startVal = 1
        endVal = 5
        For var = startVal To endVal
            MsgBox("Message Box Shows " &   var &   " Times ")
        Next var
    End Sub

End Class

When you execute this program , It will show messagebox five time and each time it shows the counter value.

If you want to Exit from FOR NEXT Loop even before completing the loop Visual Basic.NET provides a keyword Exit to use within the loop body.

  
For var=startValue To endValue [Step]
   [loopBody]
   Contition
   [Exit For]
Next [var]

VB.NET Source Code


When you execute the above source code , the program shows the message box only three times .

VB.NET Program Flow Control Related Contents
How to use IF ELSE END IF in VB.NET
How to use FOR EACH loop in VB.NET
How to use vb.net While End While loop

VB.NET Related Tpoics
Microsoft .Net Framework Tutorials
VB.NET Language Basics Tutorials
VB.NET Program Flow Control Tutorials
VB.NET Collections Tutorials
VB.NET String Tutorials
VB.NET Files Tutorials
VB.NET Excel 2007 Tutorials
VB.NET Crystal Reports Tutorials
VB.NET Communications Tutorial
VB.NET ADO.NET Tutorial with source code
ADO.NET Data Providers help and Tutorial
VB.NET ADO.NET Dataset Tutorial
ADO.NET DataAdapter and Dataset
VB.NET ADO.NET DataView Tutorial

Search here for more Vb.Net Source Code :


   Categories

    HOME
    VB.NET

 
 
 
   













  |  Home   |  SiteMap   |  About   |
net-informations.com (C) 2008 All Rights Reserved