BackgroundWorker IsBusy Property Seems To Not Work Properly?
Dec 2, 2009
I'm using the IsBusy property to determine when a backgroundworker has completed. In the RunWorkerCompleted event I assing the result of the RunWorkerCompletedEventArgs to a public variable within the module where the backgroundworker events reside. The trouble is, the IsBusy property occasionally becomes true before the public variable gets assigned the value of the RunWorkerCompletedEventArgs. I experimented with putting a Threading.Thread.Sleep(10) after the IsBusy property becomes true and it seems to fix the problem. But it really doesn't seem right that I should have to do this. What is wrong here? I have placed the backgroundworker events in a component that is instantiated from the windows form, instead of placing the background worker events within the code of the form itself.
Here is my code;
Function SendAndWait(ByVal IntegerArray() As Integer) As String
Component.BackgroundWorker.CancelAsync()
Do While Component.BackgroundWorker.IsBusy
[code]....
View 1 Replies
ADVERTISEMENT
May 23, 2011
I have not used Backgroundworker before and this one has me stumped. I have run examples (this is based on one from MSDN) and read what I could find, but I just can't seem to make this work. I am sure it is something simple that is wrong with my code, but don't know how to go about troubleshooting it. What happens is that it goes to the startthread() sub dim the object and sets the two variables and then bypasses the last line that starts the worker process. I'm stumped.
Here is the original code that works just fine, but hangs up my app (hence the need to run a background process)Above the is an Imports RARNET to support this:
[Code]...
View 3 Replies
Aug 21, 2011
this is my code:
Private Sub BackgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
For i = 0 To 1000
[code]....
View 2 Replies
Jul 21, 2011
Do you know how to work backgroundworker with this code? The request would be as I pulled out of google with a background worker and if so it is possible to collect links from google pagination.
[Code]...
View 1 Replies
Mar 8, 2012
My VB app will not work properly on a Windows 7 64 bit PC.When I launched it on the Win7 PC it will open up OK but when I open a crystal report, the form page comes up ok but the report is missing.Then I get a pop up window asking me for a user name an PW:
[Code]...
View 9 Replies
Dec 12, 2010
But I am facing problem Incase of vb .net .I am not able to add Ocx Control what should I do,
View 3 Replies
Nov 9, 2008
I am using a backgroundworker to start ffmpeg and trying to use a progressbar.ProgressBar1.Value = e.ProgressPercentage does not seem to work probably because the way ffmpeg uses standard error to report progress. I think i could use the output text to do the trick. the output.Seems stream 0 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 29.92 (359/12) [code]
View 1 Replies
Apr 14, 2011
I have a long running process running in a backgroundworker, and want it to report progress to the user, and update a checked listbox as the items are discovered. The reportprogress is called, and the statements executed (placing a break in the reportprogress routine), I can see the control valuse change, but the change is not reflected in the dialog. Here is the reportprogress routine I'm using:
Private Sub BackgroundWorker2_ProgressChanged(ByVal sender As System.Object,
ByVal e As System.ComponentModel.ProgressChangedEventArgs) Handles BackgroundWorker2.ProgressChanged
Me.newlabel.ForeColor = Color.Cyan
[code]....
View 8 Replies
May 17, 2010
I need to check if a label starts with a certain text, but it wont work!Here is the code I have:
Dim str1 As String = Label1.Text
Dim value As String = "abc123"
If str1.StartsWith(value) Then
'do something
end if
May I also add that the label i'm checking (the text inside it) has no spaces, i don't know if that makes any difference.
View 5 Replies
Aug 17, 2009
I tried so many times to convert this to DO UNTIL LOOP unfortunately it does not work properly can you help me?
Heres: the code
CODE:
View 7 Replies
Oct 31, 2009
i've got a problem here whereby my ctype doesn't work.firstly, to replicate my case briefly, i've created an extension of control class
[code]...
father.getheight 'compiler writes: Panel class doesn't support getheight, but I've already converted it to a Control with CType!end sub of course if i dim father as Control it works perfectly, but in my case father may be other objects as well that aren't controls so I had to dim father as a general object, is there a fix so i could properly convert father into a Control object?
View 1 Replies
May 24, 2009
i want to use the following function
Dim
buffer() As Byte = System.IO.File.ReadAllBytes( ImageSourcePath)
inside a backgroundworker but it does not retunr any byte at all while if this is places outside the backgroundowrker it works files.
View 1 Replies
Feb 23, 2009
I'm passing a collection of links to a background worker. The first time I use it in my bgw, it works fine, the second time (after a thread sleep) it says property evaluation failed.
View 1 Replies
Dec 16, 2009
[URL]The answer to the above question was to use a series of javascript calls as URL's in order to fill in a web form and submit it. I have been trying to do this automatically inside a VB .NET program with no success.The original example I was given doesn't work, presumably because you are waiting on the same thread as that in which the WebBrowser control is working:
WebBrowser1.Navigate("http://www.google.com")
Do While WebBrowser1.IsBusy OrElse WebBrowser1.ReadyState <> WebBrowserReadyState.Complete
Threading.Thread.Sleep(1000)
[code]....
The curious thing is that the check of ReadyState (or IsBusy, for that matter) in the wait loop will sometimes throw a InvalidCastException. Presumably calls to these are not thread safe? I have no idea. If I put the offending call inside a Try block, the wait loop just fails to work. In fact, it even seems the exception "persists" to screw everything up, because even stepping through the code with the try block Visual Studio freezes for a good 10 to 20 seconds (it does the same without the try block).
View 2 Replies
Aug 19, 2009
I'm working through a programming project, which should be quite easy but im stuck right at the start (relatively new to VB). I have a textbox (named textbox1) and a checkbox next to it. I want the checkbox to be ticked (.checked) when ever the value in the textbox is between 1 and 100, the checkbox to not be ticked when theres nothing in there, and for it not to be ticked when the value is < 1 and > 100. Figured a case statement would be the easiest. (this piece of code is just a validation check, basically in the real thing the user would have to enter in a value between 1 and a given number, and need to tell the user if that value is valid).
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
Select Case TextBox1.Text
Case Is = ""
[code]....
But what happens is, if I enter in the value 1 in the textbox, the checkbox becomes ticked, as it should. It tick with any values between 2 and 99 (any number not starting with 1) but the checkbox becomes ticked again when the value is 100. For any other range, say 1 to 70, the checkbox would be ticked if the value in the textbox is 1 to 7, or any number starting with 1 or 7, but not 8 or 9, or any number starting with 8 or 9.
View 3 Replies
Feb 23, 2012
I found a class that saves column order and column width for a list view but i cant get it to work properly.
Public Class cListviewHelper
Private Declare Function ListViewiColumnOrder Lib "user32" Alias "SendMessageA" (ByVal hwnd As Integer, ByVal Msg As Integer, ByVal wParam As Integer, ByRef lParam As Integer) As Integer[code].....
It saves the right number of columns but not in the order they are.It always saves them like this in the registry "0,1,2,3,4,5,6"
View 8 Replies
Aug 3, 2010
My project requires that a windows service checks up a table on a sql database(MDF) and if product existence is 0 then sends an email to some mail address and keep checking every 24 hrs.Now Im able to send mail messages but what Im not able is to make the service itself to work or at least make sure that is working.I do the following(correct me if I do something wrong or missing a step):
1. create a new project and choose windows service
2. add a timer and set to 4000 ms just to test not wait the 24 hrs lol
3. then open its event timer_elapsed and put some code on it, like a msgbox that would keep spamming every 4 secs just to test
4. at the event onstart I enable the timer by: timer1.enabled=true
5. at the event onstop I disable the timer by: timer1.enabled=false
6. right click then choose add installer
7. in the newer installed with the two objects:
a. serviceinstaller1 set its properties to: displayname: myservice and servicename: myservice
b. serviceprocessinstaller1 set account property to LocalSystem
8. build the project and install it by opening the VS console and type: "installutil c:path blah blahservice.exe" then hit enter
9. all successfull installed open the pc manager and run the service from the list and this should be the deal
Now my real problem is that by following those steps my service is sucessfully builded, installed, and started but after the 4 seconds no msg pops up so this leads me to think that is not doing anything or I did something wrong in the steps above. Is there another way to test if this service is working else than the msgbox or the log entry? Plus, Im working on my home pc which is a xp OS. I tried the same at college pcs wich are win7 and when I did install by the console it returned an error weird but in my home pc it doesnt(and I have to present my project at college at college and tomorrow
View 7 Replies
Feb 18, 2012
i just want to know how i can make this program run proberly. if you import a file in the listbox and you wanne start it whit the process.start methode it won't work. here is my code:
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
OpenFileDialog1.ShowDialog()
[code]....
My question is how can i make the process.start work properly and will the program start the file?
View 4 Replies
Jan 30, 2012
I wrote a program which is editing data from database. I used few tutorials (I`m beginer) and everything is working fine(I can make changes in datagrid). but when I`m trying to save changes made in dataset(e.g. save added record) I can not to that (there are no changes in my access database, but inly in datagrid)what is interesting when I delete record - changes are saved and record is deleted from db. where is my mistake? what is wrong? maybe some tips what can I improve in this small program?
[Code]...
View 10 Replies
Dec 16, 2011
i add this values to listbox
6
7
15
6
[code]....
but in button function when i press the key is shows me this:
15
5
6
6
[code]....
code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
ListBox1.Sorted = True
End Sub
View 2 Replies
Dec 8, 2010
i am still new to using session state, i want to convert page name into and integer according to a database table a function then compares "X" and "Y" to check if a user have the right to view this page..i know this is not the best way of managing website security, but it is like "training on how to use the session".[code]
View 1 Replies
Mar 24, 2011
I'm having a problem with this code:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
clave = Request.QueryString("cve")
If clave = Nothing Then
[code].....
View 2 Replies
Mar 17, 2012
I have this xaml:
<Canvas Width="75" Height="75">
<Button x:Name="button" Background="Olive" Canvas.Left="0" Canvas.Top="0" Width="75" Height="75" Click="button_Click"/>
[code].....
View 1 Replies
May 24, 2009
I've defined a public property in a mdiParent form
Public Property StatusBar_LastChecked() As String
Get
Return Me.Statusbar1_LastChecked.Text[code]....
Now when I run the code, the msgbox shows the current text and then the new text. BUT the actual text in the StatusBar remains unchanged.
View 5 Replies
Mar 16, 2012
Im getting "connection property has not been properly initialized" error message on command2.ExecuteNonQuery().
I Have an SQL query which displays its result in a grid view (one result only) I'm attempting to get this result to update the database with this particular result from the SQL query
[Code]...
View 1 Replies
Sep 6, 2005
I have a user control with an embeded DataGridView. I exposed the Columns property so that the columns collection could be edited in the visual designer:
View 2 Replies
Sep 11, 2011
I'm trying to make a program of mine into a multithreaded application, but I've hit a pair of snags that I documented in the following code. I can expand this stub into a more efficient version of my existing application.
[Code]...
View 3 Replies
Sep 25, 2011
this is my code
Private Sub WebBrowser1_DocumentCompleted(ByVal sender As System.Object, ByVal e As System.Windows.Forms.WebBrowserDocumentCompletedEventArgs) Handles WebBrowser1.DocumentCompleted
TextBox1.Text = ""
TextBox1.Text = WebBrowser1.DocumentText
Call baby()
End Sub
[Code]...
View 5 Replies
Mar 27, 2012
I have a UserControl that has a ProgressBar on it. The purpose of the UserControl is to be able to show the progress % on the ProgressBar as text. To do this it uses the MyBase.Paint event. To make it work the ProgressBar is made invisible and the UserControl is 'painted' with an image of the ProgressBar and then the text is painted on top. The UserControl has a Value property that is passed through to the ProgressBar.Value property.
I use this UserControl in two places, on a Splash form (not a standard Splash Screen) and also on the main form of the application. It works on the Splash form but not on the main form - by work I mean that changes to the ProgressBar.Value property cause the ProgressBar to show its progress. The cause appears to be that in the Splash form case the MyBase.Paint event is called as a consequence of calling Me.Refresh in the Set procedure of the UserControl.Value property, in the main form case it isn't,
i.e. Me.Refresh isn't causing MyBase.Paint to run.
The main form has two BackgroundWorker components. The first gets called (RunWorkerAsync) from Form_Load after the Splash form has been shown. The BackgroundWorker.ProgressChanged event updates the Value property of the UserControl and it works exactly as intended. The second gets called as a result of a user starting an operation and again the BackgroundWorker.ProgressChanged event updates the Value property of the UserControl but MyBase.Paint doesn't run so the ProgressBar remains resolutely static.
Any ideas why it won't respond to Me.Refresh in one case but does in the other? Happy to make any of the code avaialble but didn't want to fllod the first post with reams of it. Here's what I think are the most relevant code sections. First the UserControl
[Code]...
View 12 Replies
Apr 24, 2012
I'm trying to set the tab order on my form and no matter what I do, it doesn't relearn the new tab position after I change the index. It almost seems like the form is locked.
View 1 Replies
