Click here to Skip to main content
15,890,512 members
Articles / Programming Languages / Visual Basic
Article

Multithreading with VB.NET - A beginner's choice

Rate me:
Please Sign up or sign in to vote.
3.45/5 (60 votes)
8 Aug 20061 min read 382.9K   18.3K   104   92
Multithreading is a technique by which you can increase the efficiency of your program by 100%. Everybody wants to apply multi-threading in their own applications. But for beginners, it's a bit difficult to apply multi-threading properly. But it's quite easy with VB.NET.

Sample Image - mutithreading_for_beginer.gif

Introduction

Hi friends,

This is my first article on Code-Project on the topic Multithreading in VB.NET.

Multithreading is a technique, by which you can increase efficiency of your program by 100%. Every body wants to apply multi threading in their own application. But for beginner it's a bit difficult to apply multi threading properly. I had the same problem, when I was going to use it in my application. That's why I am writing this article, that beginner can easily apply multi threading in their application. I am trying to make it as simple as possible.

I am not writing this article against some ones request. Rather than, I am writing this article, as I personally faced a big problem on this topic. It was so hard to find out a good solution or help on "How to apply threading on application".

After so much study, search on google and on other forums at last I was able to apply multi threading in my application.

Multi Threading is not a critical or complex thing to do. But many people don't now how to apply it. They can get sample code, but can't implement it on their own project. Or they face trouble, when they try to apply the code in their application.

I am not writing much code here. Because, if you download the source code, provided with this article, you will find comment through out each line of coding. So I am not repeating them again here

The heart of this project is the following line of coding

VB
'The main mother class in .NET Framework to work with threading. 

Imports System.Threading  

'Creating Thread 
Dim objThreadClass As New clsThread(2, Me)
Dim objNewThread As New Thread(AddressOf objThreadClass.StartThread)
objNewThread.IsBackground = True
objNewThread.Start()
m_ThreadList.Item(1) = objNewThread 

'Receiving Message from thread
Public Sub ReceiveThreadMessage(ByVal ThreadIndex As Integer, _
                                ByVal Counter As Integer) 
    'do your work here depending on the return variables from the thread. 
End Sub 


'Sending Message from thread to the main application.
'First create a delegate (For details plz see the comments inside the codes) 

Private Delegate Sub NotifyMainWindow(ByVal ThreadIndex As Integer, _
                                      ByVal Counter As Integer)
'We need an object of this deletegate
Private m_NotifyMainWindow As NotifyMainWindow  

'Assign the pointer to the method of the main window to the delegate
m_NotifyMainWindow = AddressOf MainWindow.ReceiveThreadMessage 

'Create Argument List

ReDim m_Args(1)
m_Args(0) = m_ThreadIndex
m_Args(1) = m_Counter

'Call the notificaiton method on the main window by the delegate
m_MainWindow.Invoke(m_NotifyMainWindow, m_Args)

If this helps you, I'll be so happy

License

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here


Written By
Web Developer
India India
Hi,
This is Rakesh Mehta from India.
I am very very fond of programming (in any field).
I like to work on new technologies. Sometime, I face troubles, while looking for a new thing.
I am working as a Project Manager in Silicon Valley Infomedia Pvt Ltd. (India).
I'ld like to share all my new findings and solutions of problems with code project.

Comments and Discussions

 
GeneralMultithreading in web services Pin
usha gupta7-Aug-07 20:50
usha gupta7-Aug-07 20:50 
GeneralRe: Multithreading in web services Pin
sikunj patel7-Jan-09 0:31
sikunj patel7-Jan-09 0:31 
QuestionHow to use a main thread to start 4 sub threads Pin
Ramsky30-May-07 11:56
Ramsky30-May-07 11:56 
AnswerRe: How to use a main thread to start 4 sub threads Pin
Skylinc9-Nov-09 23:37
Skylinc9-Nov-09 23:37 
QuestionA request from "Mr. Raj" Pin
Sean Ewington2-Apr-07 9:06
staffSean Ewington2-Apr-07 9:06 
QuestionWhen do you use threading? Pin
gideon etan6-Mar-07 8:37
gideon etan6-Mar-07 8:37 
Generalproblem in Multi threading Pin
NVMehta26-Feb-07 3:10
NVMehta26-Feb-07 3:10 
GeneralRe: problem in Multi threading Pin
Rakesh Mehta26-Feb-07 5:19
Rakesh Mehta26-Feb-07 5:19 
Hi,
you can easily the code given in the sample to accomplish your task. Just you have modify the code to use with your project..

1. Simply make a Class with 2 methods.
a> sub new()
b> StartProcess() -> This methods will have the loop which will insert the rows in the database

2. Create a delegate (you will find in the sample code) in this class, which will point to the tread message receiving method of the form.

3. Within the loop, you can invoke the delegate on the form and can send the loop counter to the method in the form.

4. Create the object of this class from within the form. And dont forget to make a Method in the form to receive the message from the thread (for which you have created a DELEGATE on the class. In the sample code you will find the method, which is getting message from the thread.

5. Now create an object of the class and make a thread with the address of the StartProcess method of the thread and then start the thread

6. You front end form will start the thread, and the thread will start it work. Everytime it will go through the loop, it will post the message to you form.. and inside that method you can show the prgress of the thread.. when ur loop will be finished in the class.. pass a message to the form indicating thread has been finished.. and after receiving the message on the form.. simply kill the thread.

If you need anything more.. plz let me know
Smile | :)

Rakesh Mehta

Project Manager
Silicon Valley Infomedia Pvt. Ltd.

GeneralRe: problem in Multi threading Pin
harimv200226-Sep-12 21:33
harimv200226-Sep-12 21:33 
Generalthanks Pin
wmhp111-Jan-07 12:44
wmhp111-Jan-07 12:44 
GeneralThread Index Question Pin
eatwork9-Nov-06 12:14
eatwork9-Nov-06 12:14 
GeneralRe: Thread Index Question Pin
eatwork9-Nov-06 12:22
eatwork9-Nov-06 12:22 
GeneralRe: Counter variable problem Pin
Rakesh Mehta10-Nov-06 1:17
Rakesh Mehta10-Nov-06 1:17 
GeneralRe: Counter variable problem Pin
eatwork14-Nov-06 10:40
eatwork14-Nov-06 10:40 
GeneralRe: Counter variable problem Pin
eatwork14-Nov-06 11:21
eatwork14-Nov-06 11:21 
GeneralRe: Thread Index Question Pin
Rakesh Mehta10-Nov-06 1:13
Rakesh Mehta10-Nov-06 1:13 
GeneralSimple and to the point...thanks. [modified] Pin
Taner Riffat26-Oct-06 2:50
Taner Riffat26-Oct-06 2:50 
GeneralGreat Work Pin
sscottatciqgroup16-Oct-06 10:59
sscottatciqgroup16-Oct-06 10:59 
GeneralThank you very much Pin
guy_shlomo14-Sep-06 22:56
guy_shlomo14-Sep-06 22:56 
General:-) Pin
Yep-ItsMe18-Aug-06 14:44
Yep-ItsMe18-Aug-06 14:44 
Generalagree Pin
iwdu15015-Aug-06 10:48
iwdu15015-Aug-06 10:48 
GeneralThe GoTo's have got ToGo! Pin
Matt J15-Aug-06 4:09
Matt J15-Aug-06 4:09 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.