VS 2008 Do Something On Each Item In Listbox And Multi Thread

Sep 18, 2011

this is going to be hard to explain but ill try. Question 1. Ok i have a list box with a few items, What i want for this example is to click a button and it will start on the first item and do: MsgBox ("this is item blah blah blah") then after that it will go to the next item and do the same and then the next and so on untill all have been done. The "blah blah" should be the item so if item was to say "hello" then the msgbox would say "this item is hello" I know this would be a lot of msgboxes to close, like if 50 items then thats 50 msgboxes to close, this is just for the example.

Question 2. Ok this is where ive tryed to learn but find it really hard (multithreading) Im wanting all to be multithreaded so all work at the same time, ive tryed a few times but the only way i see it is having a **** load of subs, like if i want it to use 10 threads then ill have to add the same code 10 times or somet, im not sure.

i have attempted all this and failed big time as my way was to get the first item and use that then remove it from the listbox BUT... with it being quite fast the 2nd 1 and 3rd 1 used the same item befor it was removed and to be honest i dont really want them removed. so my attempts took like 2-3 days that was a waste of time really. I Know this is a lot to ask but im in real need of it and these 2 things have driven me half mad.

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[2008] Add Listbox Item From A Different Thread?

Jan 18, 2009

I've been trying to add to a listbox item from a different thread (thread 2) than the thread in which the form/listbox was created (thread 1).

When I check ListBoxItem.InvokeRequired from within thread 2 it is always false when ApartmentState.STA is set. When set to MTA I get an error. Thread 2 is a unique thread with different ID from thread 1.

What is frustrating is that at one point it was working fine, and then I changed some of the structure of the project and it has now stopped working (and I don't know which change caused this! It was a while ago).

This code is within a form class:

Option Strict Off
Option Explicit On
Imports System.Threading
Friend Class MainWinForm

[Code]....

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VS 2008 Multi-threding - Adding Multi-threading Facilities - Cross-thread Operation Not Valid

Feb 10, 2010

I'm adding multi-threading facilities for the first time. I have a function that is wrapped to be run in a separated thread. This function retrieves data (text) from a combobox and it works for sure without multi-threading.

When I call it as multi-threaded, I get the following error when I try to retrieve the data from the cmobobox: Cross-thread operation not valid: Control 'cmb1stBL' accessed from a thread other than the thread it was created on.

It looks like a restriction of thread-safety... I assume that the child thread cannot read from his parent, to make sure that he doesn't change his parent data. So how can I read the data from the combobox? Should I read the comoboxbox data before calling the child thread?

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Oct 25, 2011

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Nov 3, 2010

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Apr 9, 2011

I'm working with VB 2008 and I have a problem when using multiple listbox. For instance, I have 3 listboxs (StudentID, Surname, GivenName) and all of them are related to each other. I would like to allow users to remove a specific item by typing StudentID. Then StudentID, and two related data Surname and GivenName will be deleted also.

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I've been trying to feed a multi line textbox into a string array then check item by item if a string contains part of it.

[Code]...

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VS 2008 : Get The Multi-thread An Existing App?

Mar 17, 2009

I have an application which is working. Basically you put in the PC name/ip and it returns the logged on user. I am happy with this part. There is also an option where the program can read a text file of PC's. It will then create another text file with the name of the logged on user next to each pc. This part works, however the program is non-responsive during this time (there is a progress bar, so you can tell it hasn't stalled). I would like to multi-thread this part of the app if possible, Just starting the related sub procedure as a different thread would be a great start - I'd like to start a new thread for each pc in the list to be scanned (if this is recommended) however I imagine this might be slighly complicated...The part I'm referring to is the Sub Procedure "ReadFile". This then calls the Sub Procedure "CompareUserList".

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Mar 10, 2010

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VS 2008 [Multi-threading] How To Run This Code In A Separate Thread

Apr 21, 2009

I am creating an IDE for a game script with similar functionality as the Visual Studio IDE (at least, some of it). The game script consist of code that looks visually a bit like C code. It uses braces to define the start and end of a 'class' and uses nested braces to define the start and end of an 'event' in a class.

What I want finally is to have two Comboboxes above the text editor, one that lists each Class and the other listing each Event. The comboboxes should also show the Class and Event that the caret is currently in, just like in Visual Studio.I have attached an example of such a script (you can open it with Notepad).However, here is a short example where you can also see how I "defined" classes and events:

class1
{
event1
{

[code]....

As you can see, the classes are the 'names' of each block of code, defined by matching braces { }. The events are the names of each nested block of code, also defined by matching braces { } but inside a class. There is only one level of nesting.As you can also see, the layout can follow the standard C-style layout, or a slightly different layout (using the opening brace on the same line as the class/event name), or even a completely chaotic mess. As long as the braces match correctly, the code is valid.So in short, the large blocks are classes, while the nested blocks are events.

What I want to do, is parse an entire script, and store all the Classes (and eventually, also all the Events, but let's forget about them for now). I want to store the Class name, start position (defined as the start index of the name), end position (defined as the index of the closing brace) and the full text (defined as the text between start and end position, so including the name).

vb.net
Public Class clsClass
Private _Name As String

[code]....

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Oct 11, 2011

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Yes, below code in VB.Net , VS 2010 Winform project can throw the exception "Cross-thread operation not valid: Control 'Form1' accessed from a thread other than the thread it was created on."

[Code]...

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VS 2008 - Multi-thread Two Loops So That This Process Is Running At The Same Time?

Jun 28, 2009

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[code]...

I have 2 connected GSM Modem in usb port.That codes will send SMS in all contacts in my ListBox.

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May 26, 2011

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Feb 1, 2010

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[Code]....

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have this code that gets the first item from the listbox

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
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[code].....

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I had followed the Example on mulit-thread in MSDN, but add a loop in my implementation. But seems like the multi-thread is not working.

Private
Sub
SboE_Start_Btn_Click(ByVal
sender As
System.Object,

[code]....

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Oct 19, 2010

I'm experiencing an error which complexity and way to approach I can't quite understand.. It looks like two threads not able to work simultaneously.The first thread is the normal program thread, and the problem occurs when the user clicks a button. This sends some messages through a method (PlaceOrder) of an API library object. This method is called 2-3 times in a loop. Handlers have also been added (on program startup) to receive callbacks on events raised by that object, and this is the 2nd thread that contributes to the error.

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AddHandler ibclient.Error, New EventHandler(Of ErrorEventArgs)(AddressOf client_Error)
..while later, related to the freeze, I have:

ibClient.PlaceOrder(....)

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Private Delegate Sub SetRichTextBoxInvoker(ByVal message As String)
Private Sub OnLogUpdate(ByVal message As String)
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Nov 19, 2009

Im trying to get the Text of a Item that is in a listbox. I basically want to use

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Sep 13, 2010

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VS 2008 Searching In Listbox Item?

May 15, 2010

i have this code

vb
For Each sWord As String In listbox1.Items
If textbox1.text.Contains(sWord) Then

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new
new text
text

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Aug 19, 2009

Is there a way to see if an item is selected in a listbox?

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Feb 29, 2012

Has anyone any ideas of what these errors mean and how to fix them?

Error 1 Overload resolution failed because no accessible 'New' can be called with these arguments[code]...

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[Code]...

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Jun 2, 2011

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dim items as new list(of string)
private sub button_click()
start parsing thread
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[Code]...

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