The scenario is that an ASP.NET webforms page will call a web service in an async manner to make about 8 web service calls to various providers for data. I would like to run them in parallel to speed things up. I also need to wait for them all to come back before moving on.
View 1 RepliesI need to retrieve multiple objects from an external system. The external system supports multiple simultaneous requests (i.e. threads), but it is possible to flood the external system - therefore I want to be able to retrieve multiple objects asynchronously, but I want to be able to throttle the number of simultaneous async requests. i.e. I need to retrieve 100 items, but don't want to be retrieving more than 25 of them at once. When each request of the 25 completes, I want to trigger another retrieval, and once they are all complete I want to return all of the results in the order they were requested (i.e. there is no point returning the results until the entire call is returned). Are there any recommended patterns for this sort of thing?
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I need to make an asynchronous call to a method which for the sake of simplicity counts from 1 to 100. If an exception is thrown during the methods counting process, lets say at 50 I need to stop the methods execution, dispose of a few objects and restart it at 51 but have no idea how to go about it.I basically need to raise an event from the method to the main thread and restart the asynchrounous method.
View 3 RepliesI just have a simple vb.net website that need to call a Sub that performs a very long task that works with syncing up some directories in the filesystem (details not important).
When I call the method, it eventually times out on the website waiting for the sub routine to complete. However, even though the website times out, the routine eventually completes it's task and all the directories end up as they should.
I want to just prevent the timeout so I'd like to just call the Sub asynchronously. I do not need (or even want) and callback/confirmation that it ran successfully.[code]...
I have problem setting up the mock to fail if the user has attempted to log in three time with failure. My code looks like this[code]...
View 2 RepliesI had the idea of making a program that would take a list of URLs, display each one, and then let me save the web pages as they came up. So I wrote the following few lines of code. The interesting thing is that they don't work: (vb express 2010)
Imports
System.IO
Public
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after finally fixing many problems with my program, and finally fixing it so it could run in a backgroundworker... I started to learn INVOKE but a small problem with this. Im not sure.. do I have to INVOKE for EVERY component of a FORM I want to modify? or is there a way to group all the invokes into a single big one?or a groupbox could work?
If progreso1.InvokeRequired Then
progreso1.Invoke(New updateprogressbardelegate(AddressOf updateprogressbar), New Object() {Me.ProgressBar1, valorprogreso})
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I have a VB2008 music-player program with a listview that acts as a playlist. I created Windows Shell Context Menu entries in the registry for MP3 etc files, so if I right-click such a file in Windows Explorer it gives the option: Play in MyProg. If multiple files are selected in Windows Explorer and sent to be played in MyProg, the first one must be sent to the music player (part of same prog) and the others must be added to the playlist (listview). For this reason I must know whether a commandline call is just a single one or whether other context menu calls will follow.
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2. FunctionLayer -deals with Common Operations which get results from DataLayer and return results to Forms.3. User - deals with User. (For Reusing the User Class in other projects, i have separated this class)Here in Class2 - I have an instance of Class1( ie., DataLayer) for DB Operations.imilarly in Class3- I have an instance of Class1( ie., DataLayer) for DB Operations.Now in my form, If i create Instance of Class2. But When I need user functionality in this form, I have to create an instance of Class3 to this form.
View 6 RepliesI am venturing into WPF - first time in (VB).NET - and trying to re-create a project I started in MS Access VBA. It basically scrapes a series of pages within a web application. As you may have surmised I am having trouble with the LoadCompleted event.I have searched and found some information on it, but the "flow" of the code only lends itself to waiting for one page to load.url...All of the code execution is run in the DocumentLoaded event which works fine when you just need to navigate to one page and execute code. But I need to perform a series of these cycles for my application. How can I reliably wait for the document to fully load while still keeping the code execution in the same Sub AND not locking the UI thread? [code]That's it. Repeat for n times. my interactions with each DOM are significantly different.
View 2 RepliesTrying to make a call to another forum to chance some text boxes on it and update it. I had it working I thought but the values were not holding when I closed the box so I came up with this solution but Im getting null exceptions.[code]....
View 11 RepliesOnce I click Sign in, I want the application to test to see if the user has internet. If it does I want it to call another sub. If the network is not available I want a message to come up and say Error, no internet connection.
This is what I tried but can get it to work If My.Computer.Network.IsAvailable Then Call testnet()
else Messagebox.show("Error", "Truoble connecting to data base")
i wanna make a program with vb that can make pc to phone calls and i wanna know if it is possible with vb or if i need another program because im new to this programing thing
i added a tool in toolbox called phonecall but however i cant use it i dont know why
I know how to call a simple old fashion asmx webservice webthod that returns a single value as a function return result. But what if I want to return multiple output params? My current approach is to separate the params by a dividing character and parse them on teh client. Is there a better way.
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What the Win32 API is? I have looked around but no where really outlines what it is. Is it basically a set of procedures, outlined by Microsoft for programmers in order to get services from the operating system? In essence is it the equivalent to making system calls abd and library calls in UNIX? And yes I now Windows makes library calls too.
View 2 RepliesI'm fairly new to .NET programming. I am trying to check if there are settings in a database table and if not, create some default settings. The problem is that when there are no settings I need to make two calls with the datareader and it keeps giving me problems. I originally was only using one datareader but made two to attempt resolving my issue, didn't work. Then I tried closing the datareader and I get errors because it returned a nullreference.
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I am trying to create an application that will make calls to an API. I want this process to be fully automated to run a few times a day. What kind of application in vb.net can be automated? I've created windows applications in the past, but never automated anything.
View 8 RepliesUsing the code example on the Twitterizer website I am trying to post a tweet to twitter with this code:
Dim asyncResult As IAsyncResult = TwitterStatusAsync.Update(
tokens.Tokens,
Tweet.Text,
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I want to use a database table as a a queue...but the processing of these messages cannot be done from the database.I have a table that stores the requests i get from a .Net component. I now have to read the data from these tables and make http calls to 2 webservices. Based on the response received from the webservices, the data gets archived or deleted.I had a few specific questions:
1. How do i make sure that if i pick a record for processing and the http call fails I should be able to go on to the next record, and then come back to this record at the end of the run
2. Is there an alternative to using the database as a queue(like MSMQ etc.), which option is better
3. I want to maintain an audit trail of the record status. Is creating a trigger to log the changes before the edit the best way to do it?
I have been using DBTransaction for my current projects that access a single database. However, I read some documentation on TransactionScope and was wondering in which scenario would using TransactionScope be better? Or should I be replacing DbTransaction calls with calls to TransactionScope?
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In my program, I created a list of a class that contains 5 picture boxes, a button, a label, an identifier, and some other stuff. I've got roughly 65 of these in this list. I'd be stupid to hard code all that in. The identifier is a 2nd way of identifying which specific location I'm working on.
Anways, all this is created at compile time. Works perfectly fine.
I then manually start a background worker that pings a collection of components. Based off the success of those pings, the picture boxes are enabled or disabled. Basically a proactive way to see if a collection of devices over multiple locations are actually working.
It's the background worker that fails because of thread-safe calls.
Private Sub bgwStatus_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles bgwStatus.DoWork
Dim status As Integer
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how I can control the tool tip popup or make calls to the text that displays based on a integer value. I'm wanting it to display a text based on a interger value inside an if statment for a picture box. So if the ingteger = 1 then tooltip.text = "" else tooltip.text = "" but that is not the correct syntax.
View 2 RepliesI've created a Delegate that I intend to call Async.
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I have an application that I am reworking. It has many reports and a pain to compile and roll out.I'd like to make a root user interface that "calls" the functions and subs remotely.I was concidering pulling them and making formless exe's of them, passing the needed criteria via command line. Yet still be able to update and control them.
View 4 Replieswhat im trying to do= make a program that will make multiple accounts
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ok what i type in textbox(es) "1" i want it typed on a "3"{a website=www.justin.tv/signup} when i hit the "2"[button1]i really dont have any idea what im doing i know ill need to have a webrowser to load the justin.tv/signup but i have no clue what the name of the boxes are called on the webpage
I have this code obtaining data from a sensor that is sending a string that contains 4 numbers separated by a tab and terminated by an end of line/ I am trying to use an asynchronous callback to get the data over TCP. That problem is that the callback function is not grabbing the complete string. Sometimes it will, other times it gets half in one retrieve and half in another. I need the callback to hold off until it gets a newline character.
Code:
Public Sub readVaisala()
Dim ip As String = "192.168.1.30"
Dim portNumber As Integer = 23
Dim time As Int32 = Now.Second * 1000 + Now.Millisecond
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How can I set up an asynchronous web service in asp.net?
I want to call a webservice to post some data to a database, but I don't care if the response failed or succeeded.
I can use .net 2.0 or 3.5 only and it can be in vb or c#.
I have a small VB.NET application built using VS 2008 and .NET 3.5.Very simply, there is a timer that kicks off every few seconds to download an XML stream from the web. I look at this stream and manipulate it.The problem I am facing is that the remote web server may not respond in a timely fashion to the following line of
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How can I implement asynchronous calls so that the my application can behave without locking up?
I have a class with a mthod which does a a time consuming task. I know how to start the method in a separate thread using the Threading.Thread class. What I want to do is use callback so as to have the method report its result to another method when completed. I chose to use the asynchronous Begin/End call pattern.
Private Function BeginConnect(ByVal URl As String, ByVal callback As AsyncCallback, ByVal state As Object) As IAsyncResult
'Some Code
End Function
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i'm creating an Asynchronous socket programming in vb.net. i've utilised the code from Asynchronous client and server code frtom the following links:m a new user so could post only one link fully)When I try to connect the for more than one client the second client always waits until the first clientcompletes the call. i want the clients to accept calls at the same time
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