I am having a problem with the cellvalidating event constantly firing when the datagrid is refreshed (since the trigger that fires the event is the originally selected cell losing focus).I would like to remove the event handler for this at certain points of my code so that it does not fire but the examples I have come across on MSDN don't appear to do anything, so I guess I must be doing something wrong.[code]
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I have a datagridview and the cell gets validated in the validating event;
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remove an event handler from within the event handler?
I have a class that gets data from a hand scanner. When the scan is complete and the data is validated, the class fires a custom "ScanComplete" event and returns the data in a custom EventArgs.
In the calling program, I'm creating an instance of the scanning class and adding a handler for the "ScanComplete" event. In the event handler I get the data that was scanned and then remove the handler.
It seems to be working but it feels wrong to remove the handler while I'm running inside the handler. Will this cause a problem?
I am writing below code for validating compulsary field account no. in form.User's requirement is set focus back on field when error comes :
If txtAccountNo = "" Then
MessageBox.Show("Account no filed can't be left empty")
txtAccountNo.SetFocus
Exit Sub
End If
It's working properly. But suppose user don't want to fill form and exiting from application.Message box keep on appearing till user enters account no.
Some controls are dynamically created within a panel. Their event handlers are attached
Dim btn as new system.windows.forms.button
with btn
'set properties
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I have a TableGridLayout (6 x 6) which host 36 buttons created at design time.From the 36 buttons, only a handfull maybe needed at anyone time depending on data retrieved from an SQL database.Everytime I need to 'clear' the grid to populate with new items, I clear the text of each button, make it visable if required and then upadate with the new text.On every pass if a button becomes active, I add an event handler to the button like this.[code]...
View 4 RepliesI'm writing a small 2D engine that uses Lua to control it. I've been setting events up in between the Lua and the VB.net for the past little while here. The problem, I've realized, is that is that I can't seem to remove the events which is screwing up quite a few things (because they are being called when they should be done with). To fix this, I wanted to add some kind of way to remove the specific event handler.
I know how to add an event handler:AddHandler Button1.Click, AddressOf Button1Clicked
But with this in mind, is their a way to remove a specific event handler in the VB.net? I didn't explain this very well: If I have this:
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I have a Timers.Timer called COMTimeout, to which I add an event handler using:
AddHandler COMTimeout.Elapsed, AddressOf TimeoutEvent
however, the handler may also be:
AddHandler COMTimeout.Elapsed, AddressOf SecondTimeoutEvent
I now need to remove the handler, is there a way to do it without knowing the name or do I need to keep track of which handler as been assigned?
VB.NET RemoveHandler & Anonymous Methods
If I add an event handler like this:
AddHandler s.Click, AddressOf Panel1_Click
How can I can then remove the event handler?
Private Sub Panel1_click(ByVal sender As Object, ByVal e As System.EventArgs)
' Remove code
End Sub
I have a context menu which is shown over a DataGridView as follows below. The Context menu is shown if the mouse up occurs over the second column of the DataGridView. I also have a bunch of event handlers set up for each item in the context menu. I now want to pass the location of the cell in the datagridview to the event handlers.Do I have to pass the NewPoint() to a public variable and then translate that into a cell location within the event handler?
Private Sub DataGridView14_MouseUp(ByVal sender As Object, ByVal e As MouseEventArgs) Handles DataGridView14.MouseUp
Dim hitTestInfo As DataGridView.HitTestInfo
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I have a linkbutton that is nested in a datagrid that is nested in a datalist (yes, very strange, but unfortunately it's part of the site which I cannot change). Essentially I want the linkbutton to fire an event handler that calls Response.Redirect(e.CommandArgument)). In other words, I already have the URL that I want to redirect to, but I can't figure out how to get the event to trigger when I click on the linkbutton.
I have tried using the linkbutton OnClick events and the ItemCommand events for the datagrid but I dont think I am registering them correctly.
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This is my latest attempt where I am trying to get the datagrids ItemCommand to fire when the client clicks on the link, but it's not working at the moment.Failing this, is there an easier way to redirect the client to the correct page when they click on the linkbutton? I tried using the OnPostBackURL but the issue is that there are objects that need to be carried over that dont seem to be when I do this or when I just use a hyperlink with navigateurl set.
Is there any way to catch the textbox control in the datagrid? like catching its keypress event?
View 1 RepliesThe 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
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Can't Remove Row in datagrid on event RowValidating
View 6 RepliesI am creating a Windows Foms Application. When a form is shown, the focus is inside a causesValidation textbox. If the user presses the Escape key, the app insists on completing the validation of the empty textbox.
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How do I get a Event Handler to fire from within a nother Event Handler?
View 6 Repliesvalidating a datagrid coloumn..,i want only alphanumeric values.,symbols like -,+..etc were not allowed..folliwing is the code wht i have.,but it allows only alphabets but not numerals.
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The problem is that if you never enter anything into a cell for a new row then that cell is never validated. This is a problem because I have columns that should not be null. I am doing the check in the row level validation and storing the information about which cells are empty that should not be empty. The row level validation works fine and the row level validation error indicator goes on,(red exclamation mark at the beginning of the row) but I also need a visual indicator on the individual cells that are in error.
I am thinking that setting the HasError property for the cells that are in error should cause them to display n error style (the default red border). Is there a way to this this either from XAML (perferably) or from code?Alternatively I could cause those cells to re-validate when the row editing is finished. Does anyone know how to do this?
I have a datagrid that will be accepting data from an external measuring device via the serial port. The grid is also open to editing records as well. Part of the process of making this grid user friendly is to intercept the "enter" key and move to the next cell until there is a value in the cell. This is only for some cells, other cells can be blank. I have worked out how to intercept the "enter" key from another post on this forum. Here is the code:
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I'm trying to validate the contents of a datagrid cell against the values in a Dataset:
VB
Private Sub dgOperator_CellValidating(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellValidatingEventArgs) Handles dgOperator.CellValidating
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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].....
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 have searched alot but can only find info on moving entire rows bound between 2 datagrids, but noting on moving single cells. I have some code below that works ok from DGV to textboxes but not from DGV1 to DGV2.
Dim i As Integer
i = DataGridView1.CurrentRow.Index
Form3.DataGridView1.Item(1, i).Value = DataGridView1.Item(0, i).Value
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When I utilize AddHandler in VB to add my own method to the Click event :
AddHandler Button.Click, AddressOf myButton_Click
I see that my code executes last - after other event handlers for the Button_Click event. Is there a way to insert my event handler in front of other events so that it executes first?
I ma using DevExpress controls (which doesnt matter for this example). I have a lookupEdit control and I never want the EditValue_Changed event to fire. Can I use RemoveHandler to do this? If so can someone give me a code example of doing this? Should I put RemoveHandler in the load event of the user control I am creating? Or does it go in the EditValue_Changed event of the lookupControl?
View 3 RepliesI want to after clicking on button2,after that if i click on button1 then msg is not displayed Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
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I have a textbox control to take some input and a button to execute something. I want the button's click event will not work as long the validation to the textbox is successful.
Private Sub txtSuffix_validate(ByVal sender As System.Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles txtSuffix.Validating
If Not txtSuffix.Text = "" Then
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When I've used the remove handler method in my code, I get this warning:The 'AddressOf' expression has no effect in this context because the method argument to 'AddressOf' requires a relaxed conversion to the delegate type of the event. Assign the 'AddressOf' expression to a variable, and use the variable to add or remove the method as the handler.Why do I have to assign the "AddressOf" expression to a variable?
View 6 RepliesI am facing a issue while using the "validating" event of the maskedtextbox. I have an MDI form, in which there is a main form and a form acting as bottom bar. The bottom bar comprises of buttons for moving to "previous" and "next" forms. If suppose in the main form i have a maskedtextbox and the initial focus is set on it, then on the click event of the button (next; which is on the bottom bar form), it calls the validating event of the maskedtextbox twice. In the validating event of the maskedtextbox, i am checking some validations and if it doesnt pass, then i set [e.cancel = true]. just let me know the reason behind the triggering of "Validating" event twice?
View 1 RepliesHow to remove a handler set up by a lambda expression? According to this MSDN article, lambda expression should be assigned to variables which should be used to define handler operators. So far, I have used lambda expessions w/o variables.
For instance, the following works:
Private Sub ScaleObjectInit1(ByVal objSrc As NumericUpDown, ByVal objTgt As FrameworkElement) ...
AddHandler Me.upDnScale.ValueChanged, Sub (sender As Object, e As Object) ScaleObject1 (sender, e, objTgt)
End Sub
Private Sub ScaleObject1(ByVal sender As Object, ByVal e As Object, ByVal objTgt As FrameworkElement)
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