Create A New Instance Of Webbrowser Class Inside Of A Worker Thread?
Jan 14, 2009Is it possible to create a new instance of the webbrowser class inside of a worker thread?
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Create Instances Of Forms Inside A Worker Thread?
Nov 3, 2011I am trying to create a new instance of a form if its not allready been created the only problem is is that the instance creation is inside a worker thread.[code]...
View 2 RepliesVS 2005 Class Api Needs To Get A Handle On Form Elements In The Main Worker Thread
Sep 4, 2009I have a standard windows application called winap. I have a com component which acts as an api to the winap. I have a class in winap call classapi which has all the methods that the api calls and all works well. The problem is that one of the methods in my class api needs to get a handle on form elements in the main worker thread. Whenever I try to access an existing form I keep getting null because the for exists in the main worker thread and my api call is in a seperate thread.
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Background Worker Create Second Thread For Progress Bar?
Apr 6, 2011I have searched the forum and found several forums related to the backgroundworker thread but have been unsuccessful in finding my answer.My objective is to display an animated gif or progress bar while the program is executing a particular method which can take upwards of several minutes to complete. I cannot get the second thread to run the progress bar while the main progrem is executing the time consuming method. I have created a demo based on another thread and can't seem to get it to create two threads. I was attempting to get the backgroundworker to execute the progress bar while my main code runs on UI thread.
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How To Assign A Different Reference To A Class Instance From Inside The Class Code
Jan 18, 2011my proble is the following: I have a class MyClass and another class Modifier, which has a method ModifyMyClass(ByRef mc as MyClass) that receives a MyClass instance as ByRef parameter to modify it. A smell of the code is:
[Code]...
Write In Worker Thread In A Data Table And Rich Text Box in Main Thread
Mar 4, 2009I'm creating a Client Server application which involves theServer running some scripts in clients and getting back results in an automated way. In Server, other than Main thread, i have 2 worker threads, a) one monitoring response from clients and b) the other scheduling next available job to respective client which executes that job. The issue here is ,I want these worker threads to write the status of their work in the UI(which comes under Main Thread). Also i need to write things in worker thread in a Data table and Rich Text Box in Main thread. But, I can't do so, since it has been blocked to access one thread's function or property directly from others. Is there any work around to do this?
View 8 RepliesVS 2008 Object Data - Create A Class And Create A Instance Of CarData?
Nov 28, 2010I want to create a class is it where I can do...
[code]...
How do I do this? Do i create a class and create a instance of CarData? but how do I add Color and Year etc to it?
VS 2010 Class Create Another Instance Of The Class Itself?
Jun 11, 2012I want to create a class that will "search" for something. Basically I load up the "search item" when the class is created and inside the class is logic to do the "search". The result of this logic will be more "searches" that I want to start. How can I have the logic in the class create another instance of the class itself?
View 3 RepliesCannot Create An Instance Of My Class
Feb 24, 2010I am working on an ASP.Net 3.5 solution that I did not originally build. I added a class file named Incident.vb to the App_Code folder like I always do.But in my code behind of a web page, I usually create an instance of a class like:
Dim oIncident as New Incident
But after I type "New", normally I would see my class file he intellisense but I do not. So it does not seem to be able to find Incident.vb. I have not seen this behavior before. Trust me, my class is correct. I have created many class files like this.[code]...
Asp.net - How To Create Instance Of Class In Different Methods
Aug 3, 2011Do I have to instantiate description every time for different method? Or should I use static? Here's how I'm doing this now: What is the best way of handling this kind of situations. it seems that I repeat this line:Dim description As BLLDescription = New BLLDescription() without any good reasn.
Protected Sub Button8_Click(sender As Object, e As System.EventArgs) Handles Button8.Click
Dim description As BLLDescription = New BLLDescription()
[Cdoe].....
Cannot Create Instance Of Abstract Class
Mar 31, 2010I am trying to compile the following code and i am getting the error[code]...
View 2 RepliesVS 2008 When To Create A New Class Instance
Jun 22, 2010I understand if i was to create my own class i would need to declare a variable with the new keyword to create an object to access the encapsulated methods properties etc, unless they were declared shared.
dim myVar as myClass = new myClass
But in this next example is where i have become confused. i have added the mschart control to the form and used the hittest function with the following code.
Dim myVar as hittestresult
myvar = me.chart1.hittest(e.x,e.y)
Why wasn't it necessary to create a new instance of the class 1st. Does the hittest function return an object or a reference pointer to the object. To clarify what's the protocol for when & when not to create a new instance of the class in use.
Create A New Instance Of The Moblist Class Each Pass?
Jan 13, 2011I have an application that reads another processes memory.I initially had multiple scanning threads for the various areas I needed to read.This was processor intensive so I decided to go with the observer pattern.All was well except that I am having a weird behavior.Here is what is happening.I have 2 radars (overlay and mapped)Both have a watcher class that attaches to the memory scanner and is notified on a new list of mobs.so I open radar 1 (mapped) it attaches it's watcher to the scanner and waits for mob list update notifications
Open radar 2 (overlay). same thing happens and another watcher is attached.all is well and good so far.Now there are properies on the mobs in the list, one of which is IsFilteredOut.This property is set in the radar code after it receives the list. Now the weird behavior is that no matter what I do, the second radar to be opened changes all the properties of the mobs in the list of both radars.It is as if I am passing the list by ref, but I am not.I actually create a new instance of the moblist class every time I pass the list.Here is the notify code. As you can see I create a new instance of the moblist class each pass.
Private Sub NotifyMobListUpdated(ByVal Mobs As List(Of MobData))
If Mobs IsNot Nothing Then
For Each w As Watcher In _watchers[code].....
.net - Create A Variable Of An Instance Object Of A Class At Runtime?
Sep 29, 2011I am trying to create new variables inside a class after creating its object at runtime. The problem is that I don't know the variable names or the value beforehand so I have to create the new variables at runtime.
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This is a more elaborate explanation of my code. If you observe that in the Eval function I have tried to evaluate Fval(abc). Now the object array abc is not declared in the Test class because it existence is not known beforehand. What I want to do is create an object array abc of length 2 and populate it with some values and when Fval(abc) is called then then the value of index 1 should be the return value of Eval fucntion.
Create A New Instance Of Security Class For Every Form In Project?
Feb 19, 2009I'm creating what I believe is an mdi app.I have a login form.I have a class for security.My login form creates an instance of the security class. There are all kinds of security parameters for each user (permissions to different things, etc.)These parameters are part of my security class.Once the user logs in, many other forms will all be opened and closed within the main mdi frame.All of these other forms need the information of the security class to know what the user has permission to do.Do I have to create a new instance of security class for every form in my project? Isn't there a way to store this stuff globally somehow. Retrieve once from the db at the start of the app during login and just get it from this global area everytime?
View 2 RepliesDynamically Create An Instance Of A Class From A String Input?
Apr 24, 2011I have this class Framework.Asd.Human with a public empty constructor. and i want to be able to dynamically create an instance of it from a string input "Framework.Asd.Human". Is this achievable? (in java and C#)
View 2 RepliesMake Constructor Public And Allow Anybody To Create An Instance Of Class?
Apr 6, 2009I have a class inside a class.I need to expose the properties of the 2nd class to other classes, therefore it is public.However, I do not wish other classes to be able to create instances of this 2nd class, it should only be instantitated from its parent class.I thought I could resolve this issue by making the constructor of the 2nd class private, but this even prevents the parent class from instantiating its child class! How can I work around this, do I have to make the constructor public and allow anybody to create an instance of the class?
View 3 RepliesCreate A New Instance Of The Windows Media Player Class In VB 2008 Code?
Dec 13, 2009I do not want a Windows Media Player control on my form. I am making an alarm clock. I have tried this: Friend WithEvents WindowsMediaPlayer As New Microsoft.Win32. But I do not see a Windows Media Player member. I also asked on the MSDN VB Forum.
View 1 RepliesCreate A Sub Main Inside A Class Which Is Itself Part Of A Project
May 17, 2009why, when i create a sub main inside a class which is itself part of a project, i need to create it as a shared sub like this.[code]
View 2 RepliesError On Worker Thread
Dec 27, 2009I have some class that splits some work onto multiple worker threads. To be more specific: the class represents a download, that can have as many segments as the user wants, that get then put onto separate threads.When I run the download with one segment, it works fine. When I run it with 2 segments, the second segment encounters an error.[code]When I put a breakpoint on the if, it'll stop there, but when I go to the next line, I get an error.I don't get what's getting wrong, and got a headache after a few hours of attempting to keep track of the correct thread.Anyone an idea what's going wrong, or how I can detect it better? (This is the first time I'm doing real multi threading debugging.
View 4 RepliesUpdating UI From Worker Thread
Oct 27, 2009This is slightly different to just updating a UI from a worker thread. The object which calls the thread, calls another object, and it is this object which is is trying to update the UI. It doesn't however work.
Imports System.Threading
Public Class Form1
Public Delegate Sub GetText(ByVal sText As String)
Public GetSomeText As GetText
Public Sub New()
' This call is required by the Windows Form Designer.
[Code] .....
VS 2010 Utilizing A Class Globally - Create An Instance That Is Usable Across Forms / Modules
May 8, 2012I have created a class (pasted below in case I did something wrong) for which I want to create an instance that is usable across forms/modules. I can create an instance of the class in a single form/module no problem via DIM User as New User but how do I go about create a public instance accessible from all parts of my program?
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C# :: Co-ordinating Worker Thread Shutdown?
Nov 1, 2011I've got a List(Of IWorker) which contains a number of concretes. IWorker in turn has a Startup() and Shutdown() method.Inside the Worker class, Startup() creates a new worker thread then returns. Shutdown() presently sets a private ShutDownRequested flag and returns. The flag is checked by the worker thread (at worst every few seconds).This all works fine but at present the parent app has no way to determine if the Worker has finished shutting down.I can see a number of ways around this but am not sure what the best one is.Add a State property to IWorker. Should work but I'm going to be polling states which seems a little nasty.Make the shutdown command blocking - Would probably be my ideal solution but I'm not sure how to implement it - does the worker Sunclock a private object which Shutdown() should also try to Synclock after setting the flag?
View 3 RepliesCannot Access Controls From Worker Thread
Aug 24, 2009Here is my setup:
Form1.vb - contains RichTextBox1 and BackgroundWorker1, which calls a the Control module.
Control.vb - calls Display module.
Display.vb - calls Form1.SetTextBoxText("text here").[code]...
My observations: When the Display module calls SetTextBoxText, InvokedRequired's is false. Also, if the BackgroundWorker1 (which is in Form1.vb) calls SetTextBoxText, it works. But if BackgroundWorker1 calls a module that calls SetTextBoxText, it doesn't work.
Serial Use Of A Background Worker Thread?
Apr 6, 2012I have a BackgroundWorkerThread which I want to use serially.So some of the code in the UI thread will look like this [code]But of course I can't do the second RunWorkerAsync until the UI thread has seen the RunWorkerCompleted event indicating that the "Sequences" work has been completed (or somehow knows that the "Sequences" work has been completed).So I need some sort of synchronization between the two RunWorkerAsync calls, but whatever I use cannot hang up the UI thread because it has to be able to handle ProgressChanged events.Maybe the RunWorkerCompleted event could make the second call but I really don't like that structure.So how do I delay the second call to RunWorkerAsync (for the "Templates" work) until the background thread has completed the "Sequences" work?
View 6 RepliesUpdate UI Form From Worker Thread?
Oct 20, 2010I am new to multi-threading in VB.NET and have come across a problem whereby I am wanting to append text to a text box on a form from a service thread running in the background.
The application I am developing is a client/server listener, I have been able to get the client and server PC's to talk with each other (confirmed through MsgBox), however I am now struggling to get the service thread on the server to append the text to the textbox, nothing vissible occurs.
I have a form named testDebug which calls a class (RemoteSupport), this class does all the handshake tasks and updates the textbox with the connection data.[code]...
VS 2010 Standard Thread Vs Background Worker?
Apr 25, 2012I have a application which processes 1000's datas.. for each processing it needs to update gui and db and many variables in my application. So what i have planned is to use 50~90 background worker with my own algorithm of thread pool, synchronization and thread close.So here is it efficient in terms of memory and performance. just confused what to use.. backgroundworker componenet or standard thread.
View 11 RepliesLoop Inside Every Tables/columns In A Dbml File To Create New Partial Class?
Aug 6, 2009I have a class that add extra information about a column for linq2sql (see code below) right now, I have to explicitly tell what column I want that info on, how would you put that code with a loop on every column in every table from a dbml file? I was doing my test on a very very small DB, now I have to implement it on a much more bigger database and I really don't want to do it manually for every tables/columns it will take hours.
how it's being used:
Partial Class Contact ''contact is a table inside a dbml file.
Private _ContactIDColumn As ExtraColumnInfo
Private _ContactNameColumn As ExtraColumnInfo
Private _ContactEmailColumn As ExtraColumnInfo
[Code]....
Create A Custom Class That Has Inside An Array Of Another Custom Class?
Jan 31, 2011I want to create a custom class that has inside an array of another custom class (see my code below) but when the programm runs is crashes. Why? What is the right expression???? Plz help I'm a newbie in VB.net.....
Public Class ctrarray
Public nameclass As String
Public ctrlindex(glvar_spaces) As ctrlindexclass
End Class
[code]....
Background Worker - Cross Thread Operation Not Valid
May 30, 2011I am testing a background workder. I am running the following code for the test.
Private Sub bgwTest_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles bgwTest.DoWork
Dim a As Integer = 0
Do While a < 10 'Infinite loop
ComboBox1.Items.Add(1)
[Code] .....
But this code generates the following error:
"Cross-thread operation not valid: Control 'ComboBox1' accessed from a thread other than the thread it was created on."
