I am running a query in a thread but I can't figure out how to get the result back to the calling function. I am doing something like this:
Threading.ThreadPool.QueueUserWorkItem(AddressOf RunThread, "some query string")
Private Function RunThread(ByVal stateInfo As Object) As String
Dim myQuery As String = stateInfo.ToString
[Code]....
I'm trying to return a single object from an array of objects with linq.[code]...
View 2 RepliesI'm using webclient to download a webpage but obviously since it's on the UI thread it freezes.How can i change my class to be multi threaded using DownloadStringAsync? i can do this normally but since i am needing to return the information back to the UI thread i am a bit stuck
Public Class RequestExecutableInformation
Public Function FileReport(ByVal executable As String, ByVal ParameterStart As String, ByVal ParameterFinish As String) As String
Dim Source As String = String.Empty[code]...
in my Winforms application, there is a main thread. It is not the UI thread but it starts the UI thread. In the main thread, I'm using a Mutex to prevent the application from being started twice. That's why I'm making an exception from the rule not to use a Thread's Join method. In this case, the main thread does call UIThread.Join before releasing the Mutex. That works well.
The strange problem is: Whenever an exception occurs in the UI thread, the default Windows error dialog pops (send report, debug, close). If I select "close", the application does not quit. Instead, the main window (created in the UI thread) stays visible, but it is inoperatable. It looks as if the UI thread still does not quit, and consequently the main thread's call to UIThread.Join doesn't return either.
Though, if I debug the application at that point, the "threads" window does not show the UI thread anymore. I've given it the name "UI Thread" (surprisingly).So, why does the Join method not return even if the thread has died? Why is a window of a died thread visible?The following screenshot shows the Threads window below and the window above shows the callstack of the main thread ("Hauptthread").
If I had this, for example:
vb.net
Public Function Check
Dim FCheck As Boolean
[code].....
I am writing a program with multiple forms (for inputing loan/financial information - so they are set up exactly the same albeit a form number (ie: 1-6)) that feed into a summary page form to display each individuals form's information. When the user closed a financial form, it then feeds the information to a summary page using the code I have below: [Code]. I am new to working with functions, and have not been able to find anything that can show me how to fill multiple textboxes with them (I only know how to return a variable using the function to work a calculation). Any way that I can write a function (or any other call) for this would save me a tremendous amount of coding, and make debugging worlds easier.
View 3 RepliesI'm having trouble with a function returning two values. Each value contains a string, how can I return these values and have each one of them be stored in one independent variable. [code] I'm trying to return the hashed text with the salt and the generated salt, how can I do this?
View 18 Replies1. I would like to know why a Return statement is needed in the function in the first set of code, but not in the second(even though it still works with the Return statement). The functions are called the same way, so what is the difference?2. Why in the second code, the variable FutureValue is allowed to have the same name as the function? But when, in the first set of code, I try to rename the variable "discountPercent1"(in the function) to the function name "SetDiscountPercent", VB 2008 Epress gives the error message "The name conflicts with an existing symbol with the same name"?
Public Class frmInvoiceTotal
Private Sub btnCalculate_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles btnCalculate.Click
[code].....
What I am trying to achieve is if there is an error in cell 1 of the current row it returns to that cell. The code below tries to achieve that, but I get an error message thus:Operation is not valid because it results in a reentrant call to the SetCurrentCellAddressCore function.
Private Sub RoomPricingDGV_CellEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles RoomPricingDGV.CellEnter
If e.ColumnIndex = 2 And cellerror = True Then
[code]....
How can I handle the above warning? Should I just return nothing when an error occurs?
te Function RetrieveAllCustomers() As DataTable
Dim adapter As New OleDbDataAdapter
Try
[code].....
I have created my own ListViewItem class, and added some custom properties to it of attributes. What I have at the moment is a tooltip which shows all of those custom properties (about 18 of them).What I want to be able to do is if multiple are selected, to show a tooltip, but if a property (say Title) for all of them is "My Title" it will show that, otherwise if they are different, I would like it to show "VARIES"Is there a way of declaring a parameter in my function and return a value? [code]
View 1 Repliesi create a thread that load a function, in this function i need to read from txtbox into the same form and during the function write into another textbox the call to function is done in this way Dim t As Thread t = New Thread(AddressOf Me.myFunction) t.Start() from myFunction i read info in this way myInfo = textbox1.text and i write into textbox during the execution of myFunction in this way textInfo.text = myInfo but in debug time i have an error of crossthread.. how can i solve this problem??
View 4 RepliesA non-UI thread in my prog needs to obtain data from a UI listview control. To prevent cross-thread errors I use the following, but it freezes the prog (probably because the "Else" part is never called).What am I doing wrong?
[Code]...
I would like to create a vb form with a combo box (with song title), a text box (for song lyrics), and a button (to submit or refresh). It is linked with an access database. The combo box is populated with the songTitle field in the db (this part works fine). The text box is populated with the lyrics that go to that song The first updates fine but I can not figure out how to run a query to pass to the text box's text property. I want the user to be able to select a song from the combo box, click the button, and have the text box populated with the new song's lyrics.
Any suggestions on how to accomplish this, or a good place for a tutorial that explains the necessary elements for having vb query a database and return the results?
I have been trying to get the Alert Code from my printer at work to see what exactly is happening however each time I send an SNMP query it doesn't return any results. I am using SimpleSNMP references. The printer is a Canon iR-ADV C5045.
This is how I call the function:
Dim strAlertCode As String = SNMPQueryGet("1.3.6.1.2.1.43.18.1.1.7")
This is the function:
Private Function SNMPQueryGet(ByVal OID As String)
Dim strResult As String = "True"
Dim host As String = "192.168.1.202"
[Code] .....
I am trying to get the html response of a Kayak.com query using a WebRequest object, however more often that not the site returns no results, i just get an empty Kayak page, i have to try the request around 5 times before i get a result back. What can be the cause of this? [Code]
View 1 RepliesHow can i select using linq from a datatable where the the only results I want back (ID's) are contained in a list of integers?
View 7 RepliesSo basically, I am running through my selected path recursively and returning the results to an array.. I think.
vb.net
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim path As New FolderBrowserDialog
If path.ShowDialog = Windows.Forms.DialogResult.OK Then
Me.TextBox1.Text = path.SelectedPath
[Code] .....
I was told that to return the search to an array, I add the return toarray() at the end.
Now obviously Im not getting errors, but I am also not polling the results that are in fileslist.toarray(). I've looked at arrays quite a bit, I see their functionality if they are defined like myarray(4) with 5 declared array values... its an array with 5 value places. And to read from any one of the 5, you'd say something like msgbox(myarray(3)) to call the 3rd place in the array.
Well, as you can tell from the code, I am putting a variable amount of information into the array, How can I call that information? If I scanned a folder with 300 files, how can I call the results of that array and put them in a text file, or console, or messagebox through them? And assume I am doing it through a button click event. So, button click to read all input in the array to console or something like that.
Currently I have a gridview bound to a datatable which is populated with groups from the AD. I need to be able to add search functionality so users can type in part of a group name and have the results display only groups that fit their search criteria.
Here's what I have so far.
<asp:TextBox ID="searchParam" runat="server"></asp:TextBox><asp:button ID="btnSearch" runat="server" Text="Search" />
<asp:GridView ID="dgSearchDLs" runat="server" AutoGenerateColumns="False" DataKeyNames="cn" DataSourceID="ObjectDataSource1">
<Columns>
[code]....
I'm using Visual Studio 2005, and I have a datagrid connected to a table from an Access database.
I added 4 textboxes so the user can type search filters to search within the table and a "search" button.
Then, I created a query using the "add query" tool on the datagrid. I wrote it like: select field1, field2, field3, field4, field5, field6 from table where field1=? and field2 like "%"+?+"%" and field3 like "%"+?+"%"
and field4 like "%"+?+"%"
Both field5 and field6 aren't search criterias, so I didn't add them to the query. Once the query was created, I replaced the parameters inside the procedure with my textbox1.text, textbox2.text, textbox3.text, textbox4.text and then cut and pasted the whole thing inside my SEARCH button click event, so the query is executed when the user clicks on the button.
Now the problem is: when I search using the first field it goes ok, but when I try to search by any of the other fields it returns zero results, even though I double-checked I had written the words correctly. I don't know why it does this. I already tried deleting the datagrid and creating it again.[code]...
I have a linqtosql dbml where I dropped a stored procedure into the designer interface.
Stored procedure name:
GetUser(@userid int)
Select * from users_tbl where userid=@userid
[code].....
I am developing an ASPX web page to return results from two SQL stored procs via VB. When I execute these two stored procs, they both return valid data. But for some reason, when I run this report it doesn't return any errors, however, it doesn't return any records/data either!
Also, I can't debug it for some reason, although I can set breakpoints! This is using VS 2008, but I think reason I can't debug is I believe this is a limited version that just works for SSRS and SSIS.
[Code]...
Could the problem be due to the fact that this web page uses the same SQL connection for both stored procs? The first proc should be returned initially, and the second proc after this screen. So I don't need both stored procs information simultaneously, so I would think I could reuse the same SQL connection.
OK, I found where the problem is located. If I just comment out the Level statement in the Where clause, it does return data. So only thing I changed was that one line in my SQL code and it works. This means missing data must be due to datatype incompatibility, no? What is the problem?
[code] BUT, in code, watching the locals window for rec.EOF and rec.BOF both return true and therefore no results.Why does this work in VB Query Designer but not in code? If I remove the WHERE statement than the results return fine as expected.But its returning ALL of the results which is no good.
View 1 RepliesThe following code works just fine:
Dim wksSheetNames(0 To xlsWB.Worksheets.Count - 1, 0 To 1) As String
Dim i As Integer = 0
For Each Wks In xlsWB.Worksheets
Wks.Activate()
wksSheetNames(i, 0) = xlsApp.ActiveSheet.codename
[Code] .....
What is the best vb.net based search method that would permit me to search for i.e. "Sheet2" and be able to obtain "Cats"? I attempted to ascertain the index number of "Sheet1" with:
Dim SheetArrIndex As Integer = Array.IndexOf(wksSheetNames, "Sheet1")
Then obtain the value "Cats"
wksSheetNames(SheetArrIndex, 1)
But I received an error message:
Code Line ->>>> "Dim SheetArrIndex As Integer = Array.IndexOf(wksSheetNames, "Sheet1")"
Error msg ->>>> "Only single dimension arrays are supported here.:
Obviously I do not know how to Search and Return the results of a 2D array.
I tried to make a thread (address of function) , but vb.net didn't accept that.
is there any way to return a value from a thread ?
Sorry for new thread--i have this code, basically a loop to ping a list of ip's return the results and save them to an access db:
[Code]...
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[Code]...
Trying to find some code to assist with accessing a web service. I am a newbie when it comes to web services and don't quite get the whole how to submit the request and then read the results. I know from searches that people request a copy of the WSDL file so I have attached (SystemManagementService.wsdl)
[Code]...
I am using a class with below code, the question is how to update the label's value at UI thread from the backgroundworker?
Imports MySql.Data.MySqlClient
Public Class clsBackGroundWorker
[code]....
This is my simple code that calls a function from a class I created called "clsNetwork". The function simply pings a computer from a computername I pass it and returns the results.
Dim PingStatus As String
PingStatus = clsNetwork.PingComputer(ComputerName)
txtbox.text = PingStatus
Just so it's known, this question is mostly academic, even though I tried to use the concept in a real-world solution. I realize the example is contrived, but I believe the concept is valid.I want to write some fluent code like this:
[code]...
I realize that I can't force an anonymous type into a specific type (like implementing an interface or some other class), and I don't want the overhead of defining a specific class just to match my desired fluent name with the actual method name. So I was able to make the code work like this:
copy(my_first_file).to.Invoke(my_second_file)So there is no IntelliSense or type awareness there, and I have to include the Invoke in order to have the method run. How can I get more type safety and exclude the Invoke method, under these constraints: Anonymous Type returned from Method No additional classes or interfaces Preferably, I do not want to pass in another parameter to the copy() method that tells what type to return, unless copy becomes a generic method (but I think that means defining another class/interface, which I don't want to do)