I have a typed dataset that has some required columns. I created a form called by TableNewRow to prompt the user and verify the required selections. If the user cancels the details form I can't seem to get rid of the row that was created, it's stuck there blank.
code excerpt:
Private Sub myDataTable_TableNewRow(ByVal sender As Object, ByVal e As System.Data.DataTableNewRowEventArgs) Handles Me.TableNewRow
Dim f As New Form1
[Code].....
I have a DataTable-Property:Public Property Files() As DataTable Implements Presenter.ISearchSetup.Files
[Code]...
I have a DataTable-Property:
Public Property Files() As DataTable Implements Presenter.ISearchSetup.Files
Get
Return _files
[code].....
I have a ListView that populates some fields whenever the user selects an item. However, if they change the data in the fields and then select a new item without saving, I want to display a message box that warns that their changes will be lost, and asks them to confirm whether to continue. Sounds simple.
Unfortunately, the ListView's SelectedIndexChanged event cannot be cancelled, and it's actually called for each change in the selection. So, for example, if item 1 is selected and the user then selects item 2, the event is called twice: once to remove the selection of item 1, and then to add the selection of item 2. If you go from having one item selected to having five (for example), the event fires to remove your original selection, and then again for each of your new selections - six hits in all.
Obviously, this makes it a bugger to determine when the event should be cancelled and reset back to the original. I obviously don't want my message box appearing six times....
I was working on a custom button, in which I had to capture the event of the button, and depending on the certain conditions, either I'll block the event or pass it on the form containing my custom button.[code]Now, I do not have any idea how to block the event and not allow it to pass if the users opts for "No" in the given example.
View 1 RepliesIn an event handler of a tab chaged of a tabcontrol, I call a method asynchrounously, like this:
Private Sub tabDetails_Deselecting(ByVal sender As System.Object, ByVal e As System.Windows.Forms.TabControlCancelEventArgs) Handles tabDetails.Deselecting
' we pass pageindex so that we set the index back in case the validation fails
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Using the following VB.Net simple code to upload files in FTP, a call to WebClient.CancelAsync() doesn't actually cancel the upload.Does someone know why, and what can be done about this?
Private Sub UploadProgressChanged(ByVal sender As Object, ByVal e As System.Net.UploadProgressChangedEventArgs)
'TO-DO: Why is pbar empty?
ProgressBar1.Value = e.ProgressPercentage
Label1.Text = e.BytesSent & " bytes sent"
End Sub
[Code]...
Does anyone know how to cancel a row change in a data grid? What I want is to allow the user to modify a row in a grid. When they try to leave a row after changing it, then prompt them to save the changes before moving to the new row. So far, the rowleave event is working to prompt them to save or not. But I'd like to give them the option to cancel...which should leave them on the original row. The rowleave event, nor any other similar event, appears to have the abiity to cancel the move.
I thought about remembering the row number and just putting it back on that row...but it seems like there probably should be a better way to cancel the row change.
I'm working on this form, and I got 1 text field I am using for validation. If the user doesn't put text inside the box and he clicks the save button it throws a messagebox saying that he didn't put text inside the box, but it still saves the data to the database anyways.
If txtUsername.Text = vbNullString Then
MsgBox("All Fields are Required!!")
Me.btnSave.Enabled = False
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I have the following problem. I have a worker in VB .net (2010) which runs a shell-program. The shell program is a service and output stuff like:
Server initializing...
Server opening port...
more info...
I am able to 'catch' the output of the shell and add it to a textbox (using set text function). And I am able to Cancel the worker by clicking on a stopbutton, however when there is no more output by the shell I cannot stop the worker anymore. At least I suspect that's the case. I've tried checking for endofstream (commented section) but that doesn't work. I've also tried to same code with some test text in stead of 'clsProcess.StandardOutput.ReadLine' and that also works. So I came to the conclusion it must have something to do with clsProcess.StandardOutput.ReadLine being at the end?
Try
clsProcess.StartInfo.UseShellExecute = False
clsProcess.StartInfo.RedirectStandardOutput = True
clsProcess.StartInfo.RedirectStandardError = True
clsProcess.StartInfo.FileName = serverpath + config_executable
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How best to cancel/kill a recursive folder copy? I am looping through a number of pathnames in a list box and then recursively copying all files and sub-folders to a backup location. Suppose the user wants to cancel for some reason. I have checked that I can detect a click on my "cancel" button in a timely manner (DoEvents sees to that) but how can I stop the recursive file copy without ending the program? [code]
View 5 RepliesI am using the code below to login to a softphone. However, the login progess is a long process as there are many things that have to be initialized and checks to be made, I have only put a few on here, as it would make the code to long to post.In the code below I am checking if the CancellationPending if the CancelAsync has been called in my cancel button click event, before doing each check. Is this correct? Also if the check fails I also call the CancelAsync and set the e.Cancel to true.
Private Sub bgwProcessLogin_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs)
'
' * Perform at test to see if the background worker has been
[code].....
I have a Telerik Radgrid containing all the valid usernames and passwords that can be used to unlock functionnalities on my web page. The password is encrypted, so you have to click the row to decrypt and show the actual password. All usernames and passwords can be changed by an admin When the admin presses [ENTER] to submit the new username/password combination (instead of pressing the submit button), the new combination is actually submitted (which is fine).
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I've found some unexpected behaviour in my ComboBox, which I'm hoping someone can help me with. If focus is lost by pressing the Return key on a form which has AcceptButton set, then after handling the Validating event and cancelling the validation,the ComboBox will not drop down any more. When you click on the drop-down arrow, the list drops down momentarilly then goes away again To reproduce this, create a new VB.NET Windows Forms application. Drop a Combo Box and a Button onto the default form, then add the following code:[code]....
Run this application, click on the Combo Box, enter some random text (e.g. "asdf"), then press Return. After this, click on the drop-down arrow on the Combo Box.I'm using Visual Basic 2010 Express on Windows 7 Home Premium.
I have custom asynchronous WebRequest class that I am testing to find out how fast the request will be cancelled and found some odd results, that starting 6 WebRequests with TPL and cancelling them right away takes 25 sec, but when I used just regular background threads it took only 5 sec.
Update: Running them without cancelling takes with Task.Start 9 sec and Thread.Start 3 sec accordingly.
Imports System.Net
Imports System.Threading
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I've read thru Iceplug's tutorial on control arrays and got it working. I tried to add a new event by basically copying his click event code and calling it a doubleclick event. I used the proper addhandler and assigned the correct name to my sub. I have the click event changing the background color to blue and the doubleclick event changing the background color to green. The background color does not change to green. Why?
Heres the tutorial with my new code encased in asterisks ...
Code:
Imports System
Imports System.Windows.Forms
Public Class form1
[CODE]...
I am using VB.NET for Windows applications. What is the difference between Load event,Activate event and Enter event in the Form and in which order the above event is executed.
View 2 RepliesI'm trying to validate a few things in a form I'm building. It has a datagrid with clients info (taken from an access database) and a few textboxes where the user can type some search criteria. The thing is that those same textboxes are used to add new clients to the database and to modify a client's information if one from the datagrid is selected, so I made it that the buttons to insert and modify clients are disabled on load and thenevery time the text on a textbox changes ("TextChanged" event) they become enabled. So far so good. But then I wanted to make it so when a client from the datagrid is selected both buttons become disabled again until the text on a textbox changes (to make sure they're adding a different client and not the same one that was
selected).
I tried using the CellClick event from the datagrid to disable the buttons, but since every time a client is selected from the datagrid the info is shown on the textboxes, this triggers the TextChanged event too, and the buttons become available.So, is there a way I can tell the TextChanged event not to be triggered when the CellClick event occurs?
The event handlers in my parent class are never called though the events are raised in the child class.
The Code:
Public Class childForm
Public Event checkboxchangedEvent(ByVal checkbox1 As Boolean, ByVal checkbox2 As Boolean)
Private Sub checkboxchanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged, CheckBox2.CheckedChanged
[code]....
I'm trying to complete this airline reservation application, but having a problem in this part of the question:Creat an event handler for the FlightBindingSource's PositionChanged event: select FlightBindingSource in the class Name combobox then select position changed in method name combobox to creat the FlightBindingSource's PositionChanged event handler. Write a code to access the currently displayed flight object and pass its flightNumber to method DisplayPassengers as a decimal.This Is my code so far:
HTML
Public Class AirlineReservationForm
Private database As New ReservationsDataClassesDataContext()
Private Sub FillAll()[code].....
Eg. ""vb.net" timer event trigger on purpose". This application is meant to run at all times to download a web page every minute. To avoid freezing the UI, I read that the best solution is to move the code from a While/Sleep loop to a Timer that will be triggered every minute. The problem I have, is that the user must wait for a minute before the event is triggered:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Timer1.Interval = 60000
Timer1.Enabled = True
[CODE]...
Is it possible to force this event to occur instead of waiting for it?
I'm trying to execute different code depending on the button clicked (button 4 or 5) on Form1, but when I click on button5 to activitae the code on the Form2's Load event everything is Ok, but when I click the back button to return to Form 1 and click on the Button4 to activate the code on the Form2's Load event again, it doesn't active the Form's Load event, is there a way to form the form load event every time I access it from Form1? [code]
View 7 RepliesStarting from my understanding about Background worker control, I understands that the background worker runs the code in its "DoWork" method in a seperate thread, while ProgressChanged and RunWorkerCompleted events are executed on the main thread.In my senerio, I report the progress and under an specail condition my application displays a message box to the user in "ProgressChanged" method using MessageBox.Show(). and in "Run Worker Completed" event the application finalize some work. There the sequence is important, suppose that the message is of Yes or No type and finalization depends on it. Now when i run my application, the background worker triggers "ProgressChanged", but as soon as backgroundWorker's cancelAsync() is called the program leaves the current "ProgressChanged" method and executes "RunWorkerCompleted" code first.How can i make sure that the "Run Worker Completed" code executes only after the completion of ProgressChanged method.
View 9 RepliesProgramming language is vb.net
View 1 RepliesAs you noticed, in the code bellow, the event argument for the form click event has the type "TimedEventArgument".When the event is raised, e.Time holds the time where the form was clicked.Add the missing code in the class Form1 to make this work.You will not change anything to the methods "Form1_Click" or "Form1.Load".You will not use Option Strict On. HOWEVER, you will not do any narrowing or late binding that wouldn't have been allowed if Option Strict was on.You cannot create any new Class, Structure or Module.You cannot cast the EventArgs to TimedEventArg in any way
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Below I create an array of labels. I would like to add an click event to my labels. Can someone point me in a direction?
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I am making a function of an application that when a function is called the application will close all processes that are owned by the user and were started after a specific point. My thoughts on this would be to trigger an event in my application every time a process is started and ended, and only if the processes is owned by the user, the event should get information (e.g. the process ID, name, etc) about that process and add or remove that information to/from an array depending on if the process starts or ends. Then when a function is called end all the processes in that array.
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I have a Visual Basic Program that, when I enter data into a textbox, uses LEAVE events to update it. However, it will not update until I go to another textbox or press a button or other similar control.This also happens when using the LOST FOCUS event.How can I make the textbox update (be it doing a financial recalculation or some other custom function) happen when the user clicks/tabs out of the textbox and NOT having to click on a button or into another textbox?Do you recommend having a separate button for performing the custom functions?
View 6 RepliesCan i Know how to catch between these 2 event, Leave and Click?
I have one checking in a textbox Leave event. I will go check whether this ID is already exist in DB or not. If exist, I will prompt MSG box to user.
When I click on Close button while focus is on textbox, this textbox Leave Event will trigger first before Button Click event.
So, the form remains open without trigger Button Click event.
how to prevent this textbox leave event or how can i catch/control this situation?
In VB6 we had a code inside textBox_MouseUp to call textBox_KeyUp(-1, 0) and the signature of KeyUp was
Private Sub textBox_KeyUp(ByRef KeyCode As Short, ByRef Shift As Short) Handles textBox.KeyUp
Now when I migrate to .NET I changed the KeyUp event to Private Sub textBox_KeyUp(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles textBox.KeyUp
How can I do this call textBox_KeyUp(-1,0) now from textBox_MouseUp event?
