Threading

[cj]

I need more information to read about threading in Visual Basic.

Hopefully something linear w/o too many links to get lost in. I've been
to
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconThreading.asp
but it is too confusing. I can't find any references to STA threading
model or what exactly this is doing:

<STAThread()> Public Shared Sub Main(ByVal CmdArgs() As String)
Application.Run(New Form1)
End Sub

Thanks

 

[Cor Ligthert [MVP]]

cj,

Are you sure you need threading, as I have read from somebody active in this
newsgroup and full acknowledged by me, who wrote something as.

Multi threading is mostly in use by newbies who find it very interesting
however don't know what to solve with it.

Be aware that multithreading takes forever more processing time.

Therefore start reading it when you need it, beside the more processing time
makes it your program less maintainable.

However if you want to read something about it, than start with the
backgroundworker from version 2.0 which has at least not to much from the
last problem.

http://msdn2.microsoft.com/en-us/library/8xs8549b.aspx

I hope this gives an idea.

Cor

 

[CMM]

To complement Cor's post.... If you're coming from the VB.Classic world and
need to understand threading in relation to VB.Classic's and COM's threading
models, start here:
http://blogs.msdn.com/jfoscoding/archive/2005/04/07/406341.aspx
Then
http://www.devx.com/DevX/10MinuteSolution/20365

I can give you a canned response about what Application.Run does, but this
will be more informative:
http://dotnet.sys-con.com/read/39039.htm

 

[cj]

Cor, I would not be using threading unless I thought I had to. The
company we purchased the com components from has told me that I have to
use threading to make a TCP/IP server capable of handling many requests
simultaneously. Sounds logical to me too. I'm trying to understand
their sample programs.

 

[cj]

yes and no, I'm coming from VB4 but have never touched threading
before. Thanks for the links. I'll look at them today.

 

[Cor Ligthert [MVP]]

CJ,

Than I would ask the question more direct on TCP/IP, this subject is already
often handled in this newsgroup by the way.

http://groups.google.com/group/micr...+threading&qt_g=1&searchnow=Search+this+group

You can as well have a look at Jon's pages. However because I have read your
question, is my opinion that I think that you will not become happy from
this.

http://www.yoda.arachsys.com/csharp/threads/

Be aware that it is not as difficult as it looks like as you have seen these
pages.

I hope this helps,

Cor

 

[cj]

I'd found the DevX one yesterday. Unfortunately both are in C. Because
of that I couldn't quite figure out how it related to some sample VB.Net
code I have that uses multi-threading.

http://dotnet.sys-con.com/read/39039.htm I didn't understand.

I'm beginning to wonder if I should dump vb.net and start using C++ or
C#. It seems most examples are in C something.

 

[Cor Ligthert [MVP]]

cj,

I agree with you that it seems that almost everything written about threads
is done in a difficult way.

The problem with those two Microsoft samples is that they are good, however
seems to be made in an hour and than even direct translated from C#. They
are in my opinion both more confusing for me than educating.

I don't expect because of the new backgroundworker, that there will me much
more samples in feature using raw threading.

However multithreading is much simpler than you think in fact if there
(writing this message I saw the samples are even there)

Create a thread
Tell at which method it should start
Start it.

All written here
http://msdn2.microsoft.com/en-us/library/system.threading.thread.aspx

Than you have to sent normally (if you don't do it in some of the foolish
ways I have seen here) the information from the worker thread to the main
thread, what goes assynchone and therefore you need an assynchronous method.
For that is the Queue class an ultimate solution.

http://msdn2.microsoft.com/en-us/library/system.collections.queue.aspx

However because that there can be problems when one thread is unloading it
(in your case your main thread) and the worker thread is filling it (there
happens than two things in the same time), therefore you have to synclock it
before you unload or/and load it, which means that all actions are stopped
until the thread who has synclocked it gives it free again (end synclock).
This means that you should not use this not needed and only for that for
what it is needed.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vblr7/html/vastmsynclock.asp

About your sentence for samples in C#, the C# developers have the same
problem, they tell that all samples are writen for VB.Net.

I hope this helps,

Cor

 

[cj]

Correction: I got the DevX one you sent me confused with another one.
The one you sent me is very good. Thanks!