After searching thru BOL and various forums, I've been unable to determine how to use a backgroundworker component with a procedure that contains multiple parameters. If I understand correctly, DoWorkEventArgs is used to pass parameters. However, all the examples I have found use only one. Since DoWorkEventArgs ends in an "s", I imagine it is possible to use more than one parameter.
View 3 Repliesin my button click event i ececure
If BackgroundWorker4.IsBusy Then
BackgroundWorker1.CancelAsync()
End If[code]....
after proceess completed if press the button again.i got the following error msg
This BackgroundWorker is currently busy and cannot run multiple tasks concurrently.
I have a loop that creates several threads as such[code]...
View 1 RepliesI am writing a project in Visual Basic where I need to run several instances of the same method in parallel. I can do this using BackgrooundWorker by having several (4) copies of my code module (modules 1, 2, 3 and 4) with a call to background worker in each. I then have a Main form which invoke the 4 modules which setup 4 simultaneous background threads. Seeing as the code is the same I want to simply invoke the same module 4 times.
However when I do this I get an error from Backgroounworker that it is already busy. As I understand it this means that it is being shared. However, I have specifically instantiated it as "private" (private with events worker as new backgroundworker). I have tried running the same code in a Class instead of a Module but unless I make it public I have no way of invoking it from Main. I need to be able to pass each thread data from main for it to work on and if the class is private I cant invoke it.
I need to run multiple task in the background using backgroundwoker
e.g dim mybacgroundwokers(10) as backgroundwoker
in the backgroundworker event procedure, can i do somthing like this, cos i don't have an idea
mybackgroundwoker_dowork(,,index)
select case index
case 1
'dowork for backgroundworker1
case 2
'dowork for backgroundworker2
end select
or how do i handle multiple backgroundworker if non of this is possible with the backgroundworker, how do i do this using thread multithreading?
I have an app that is needs to access multiple web sites and sign up for accounts. I don't want to run them one by one as this would be slow as christmas so I figured that I could setup some sort of background worker and put each process on it's own thread that way the app could run each sign up page at the same time. Would using background worker be the "BEST" option to use for this type of application requirement?
View 1 RepliesI have been pulling my hair out trying to get this to work. If I step through the code in debugger it all works great. My problem is if I just run it, only the last task responds. I'm guessing I am overwriting the background working or something. I am sure I am doing a few things wrong but my code is now messy as I tried many way while searching. I know of the threadpool and .Net 4.0 tasks but having a hard time getting to do what I need.
Basicly I am writing a program (trying more likely) that takes a list of computers and pings then, then checks their uptime and reports back.This works fine in the UI thread (Obviously that locks up my screen). I can have the background worker just do this, but then it does each computer 1 by one, and while the screen is responsive it still takes a long time.
So my answer was to have a for loop for each server launching a new background worker thread. My solution does not work.I have seen other threads that I could do it, but I need to use with events to call code to update to UI when each is done.
What is the most simple way to do this?
Here is my code. Most is just copy paste + modify till I get it working right.
So In the main class I have the testworker.
(I tried using Testworker() but it said I could not do that WithEvents)
When I click the button the list loads.
Private WithEvents TestWorker As System.ComponentModel.BackgroundWorker
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles Button1.Click
[Code]...
I'm running in to a problem that I was able to fix with Application.DoEvents, but don't want to leave that in because it might introduce all sorts of nasty problems. Background: Our app is primarily a desktop app that makes many calls to a web service. We control everything but changes to the overall system design are not going to be seriously considered. One of those calls, Calculate, is used very often, and occasionally can take a few minutes to process all the data to return valid results.
[Code]...
I'm trying to create a new thread and send multiple parameters as well as a delegate to report back. In VB8 I always hate to do this because it requires either introducing a new class/structure or a delegate. Is there any better way to do this in VB9? I'm looking for a solution something like this :
[Code]...
I am trying to pass several search parameters to an LINQ expression to retrieve all entries that contain one of the search items.
Example:
Dim query = From p In db.BEW_PROFIL
For Each searchItem As String In searchItems
[code].....
I have a connection to a MS SQL database, which I understand is capable of handling multiple SQL statements in one Execution, ie
Code:
Using cmdExe As New System.Data.SqlClient.SqlCommand
sSQL = "Delete * from mytable where UniqueID=123;Insert into mytable (UniqueID, Field) values (123, 'something')"
cmdExe.CommandText = strSingleSQLLine
cmdExe.ExecuteNonQuery()
End Using
will delete from "mytable" and insert a new record all at once. This is great, but I want to expand upon that to use parameters because using string concatenation in my SQL queries is a bad idea. Now my question is this. If I add a parameter which is used in multiple SQL statements, do I have to add the parameter VALUE twice to the command object? ie, will the following code work?
Code:
Using cmdExe As New System.Data.SqlClient.SqlCommand
sSQL = "Delete * from mytable where UniqueID=@uniqueID;Insert into mytable (UniqueID, Field) values (@uniqueID, 'something')"
cmdExe.Parameters.AddWithValue("@uniqueID", 123)
[code]....
There are two questions here actually...can I add the parameters before setting the command text, and do I have to add the same parameter over and over again?
I'm looking to pass two or more parameters to a thread in VB 2008.
The following method (modified) works fine without parameters, and my status bar gets updated very cool-y. But I can't seem to make it work with one, two or more parameters.
This is the pseudo code of what I'm thinking should happen when the button is pressed:
Private Sub Btn_Click()
Dim evaluator As New Thread(AddressOf Me.testthread(goodList, 1))
evaluator.Start()
[Code].....
The code i have is working fine to pass one parameter to crystal, can someone help me pass a second parameter called "line"?
[code]...
I need to make a POST request to a server. this request must have multiple parameters, like this :
name
number
host
[Code]....
How can I do that in VB.NET. I tried WebRequest object, but there's no simple way to do that.
I need to pass four parameters to a SQL statement and i'm using the following code. It works fine for the first parameter but ignores the rest without erroring.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim conz As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data
[Code].....
I want to add a parameter to my thread call here is the code. I want to call th.Start(True, sender.Text) and Count(ByVal isRunning As Boolean) will then become Private Sub Count(ByVal isRunning As Boolean, Byval strID As String), but I can't do that. So how can I make this thread accept 2 parameters?
Private Sub btnStart1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStart1.Click
th = New System.Threading.Thread(AddressOf Count)
th.Name = "Button1"
th.Start(True)
[Code] .....
I have a little challenge. I have a report that I declared a parameter called Department that has default values like this: [Code] The problem is that when I test this (with CR10 or on web), and I select multiple values, the thing does not show the values for the multiple values. It only works when I select a single department. What should I do?
View 2 RepliesI am writing a socket client into my application. I have multiple socket connections to make to different servers.
ClientSocket(1).BeginConnect(endpoint1, AddressOf Connected, Nothing)
ClientSocket(2).BeginConnect(endpoint2, AddressOf Connected, Nothing)
Both clients call the connected sub... how do I know which one is which?
Private Sub Connected(ByVal ar As IAsyncResult)
I am using this code to pass multiple parameters but it works for only one parameter what should i do please please help me.
If TextBox1.Text = "" Or TextBox2.Text = "" Then
MessageBox.Show("Please enter Date!", "ALI ENTERPRISES", MessageBoxButtons.OK, MessageBoxIcon.Information)
Exit Sub
[code]....
How do you pass multiple parameters to a Sub which has to be invoked?Again, I've only been coding for about 3 days so please speak as if your trying to teach a child to tie his shoe.
View 3 RepliesDoObj(byval this as string, byval two as string, byval three as string) I'm trying to pass multiple parameters through a thread to this sub. I have tried this:
[Code]...
I'm trying to implement a Web API project that exposes some models. However, the way the model is retrieved isn't very RESTful. 1.Instead of having just one ID, it has a combination of 4 different ones to populate the model data by running a stored proc on the server.Dim balance as New BalanceSheet(uid, mid, eid, fid)The snippet above will use uid, mid, eid, fid to retrieve the correct record from the database.
View 1 RepliesI'm writing a query to select all records that has any part of parameter. I have one table called Employees. Some people have name like this: John David Clark If the parameter is
[Code]....
I should be able to get result back as long as there's a match in the parameters. If I use Function Contains (q.FirstName & " " & q.LastName).Contains(employeeName), I will not get any result back if employeeName is "John Clark" Function Contains looks only for next words from left to right. It doesn't match a single word at a time. So that's why I used this in the Linq to SQL:
[Code]....
I am getting error [07002] the # binded parameters < the # of parameters makers, i checked both parameters were perfect even though i am getting this error here is my code
[Code]...
i'm in the need to start a backgroundworker inside another one.Now...The first one BGW starts a for cycle, and inside this one there is the second BGW that has to upload an image to a server.The trouble is that, the progress event and the complete event of the internal BGW are never called.
View 11 RepliesBasically Commands has Parameters and parameters has functions like Add, AddWithValue, and etc. In all tutorials i've seen, i usually noticed that they are using Add instead of AddWithValue.
[Code]...
since it saves my coding time. So which is better to use? Which is safe to use? Does it improves performance?
is there a way to get the GET parameters and POST parameters in just one function or Collection in ASP.NET? Like using $_REQUEST in PHP? I'm using VB.NET.
View 3 Repliesgood example on backgroundworker control in vb.net for doing some process in background for ex a reading a doc file in textbox by using backgroundworker in vb.net?
View 2 RepliesIs it possible to set a backgroundworker as STA
View 1 Replieswhat is this BackgroundWorker and how to use it? Can it be used as a replacement to System.Threading.Thread??
View 2 Replies