I have a control that is created in the code behind and generates fine but I can't figure out how to create an event handler for it.I've found plenty of examples for it in C sharp, but none of them seem to apply to VB.
View 4 Replies
I have an assignment to complete, that for the most part is half way done, the application starts with the number zero (0) and anytime the count button is pressed, the a one (0) should be added to the output label?
Public Class CounterForm
Private Sub countButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles countButton.Click
countTotalLabel.Text = Val(countButton.Text) + 1 End Sub
End Class
I have 2 listboxes on a form. Each listbox has a few items. As you know, I am able to have 1 item selected from each listbox, therefore making it 2 selected items from different listboxes.
I want to create a keyboard + mouse shortcut so I can de-select or change the selection mode of the listbox when Alt is held down and Left button on the mouse is clicked on the selected item. Here is the code that I wrote, which does not work.
Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
If Control.ModifierKeys = Keys.Alt AndAlso e.Button =
[Code].....
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 am working with database information,and I have to add code in a dateforms , load event handler .That should set the value of the date time picker to match that of the date time picker in the main form?
View 1 RepliesI have a form that is built and loaded dynamically when File/open is selected.however I now want to use the same code to open a default file and populate the form using the Form load event to call:
Private Sub OpenToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenToolStripMenuItem.Click how would I do this? Just incase this doesn't make sense, I want the same code to run during form load as if the user selected file/open but do not know the syntax of how to call OpenToolStripMenuItem_Click() from form load.
how to pause the execution of code in an event handler.
For instance in a forms load event how can I have the rest of the programs features continue to run but wait 5 seconds before the code in the load event handler is executed?
Simply stated, I want to call the Panel1_Paint event handler from the Button1_Click event. Is this possible? If so, How? IE: Click the button and it paints the panel.
View 6 RepliesHow do I get a Event Handler to fire from within a nother Event Handler?
View 6 Replieswhen i create a new form i get this in the codePrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
View 4 RepliesHere is the code for the button click event;
Protected Sub CompetenciesButton_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles CompetenciesButton.Click
Dim con As String = WebConfigurationManager.ConnectionStrings("foo").ToString()
[code].....
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've been working on creating forms and objects through code in the the load event of Form1, truthfully theres a few questions I have under this one category but to start I want to create a button click event that will check what button was pressed then set that button to a variable. I want the event to treat the button that was clicked like it was that buttons click event.Here's a shortened version of my code (Lol if you can call this short):
[code]...
i recently received a new work pc and have installed visual studio 2010 premium on it. this was installed on my old machine as well, the only differece between the two PCs being my old one was 32bit and the new one is 64bit.With that said, when i create a windows form project and drop a control on a form, double click that control, the default event code is created for me.It is missing the "ByVal" portion of the code. Using a textbox as an example, below is the code it generates. Is there a setting that I'm just missing and need to turn on? I've been using visual studio since version 2005 and i've never seen this before.
Private Sub TextBox1_TextChanged(sender As System.Object, e As System.EventArgs) Handles TextBox1.TextChanged
End Sub
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].....
I am trying to write a program using Visual Basic 2008 Express Edition that will automaticlay generate multiple Command Buttons that have different Texts and perform different commands.For example I want to generate Button_1 and Button_2 where Button_1 when clicked enters the value "1" into a textbox and Button_2 enters the value "2" into the same textbox.I know this can be simple done by using the designer and wirting the code in the Button_1_Click, but what I want to eventually achieve is for various buttons to be generated across different Tabs in a TabControl.So far I can create a button on a windows form using code, but the button has no purpose so command is assigned to it. The code i've used is listed below:
[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?
[Code]...
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?
Is it possible to determine using VB.NET whether a certain event has any handlers attached to it? I don't own the event, in this particular case I want to know which of the items in a Windows.Forms.MenuStrip have their ToolstripMenuItem.Click event handled.
View 1 RepliesI've been looking for a solution to this for several hours now and cannot find a solution.
The Scenario:I have a masterpage baseclass (called basemaster)All of my master pages inherit from basemaster
basemaster defines an event 'Public Event HandleClickEvent As EventHandler'I have a masterpage named master1
master1 defines an event handler 'Public Shadows Event HandleClickEvent As EventHandler'master1 has a user control named usr1 usr1 has a button that raises event ButtonClicked when clicked I have a page (thePage) that uses master1 thePage has a button click event handler that it registers like so: 'AddHandler Master.HandleClickEvent, AddressOf HandleTheClick' master1 has code something like:
Protected Sub Usr1_ButtonClicked(ByVal sender As Object, ByVal e As System.EventArgs) Handles Usr1.ButtonClicked RaiseEvent HandleClickEvent(sender, e) End Sub when thePage loads I see it register the handler on master1 when the button is clicked, Usr1_ButtonClicked is fired and I step through the RaiseEvent but HandleClickEvent on thePage is never reached.
This code is part of AjaxControlToolkitSampleSite. To be exact, it is in the AsyncFileUpload control[code]...
View 4 Replieshow to add one event handler name clearallboxes that handles the TextChanged event for both examples(Customer text box and Total text box ) This event handler should clear the values in the text boxes that display the results.
View 4 Repliesi have a page which dynanically create a link when it load, after i click on the link it should loop in the database fetch all the record and display another set of link , then when i click on these link it should give me all information about this particular record it like this one
Q: when the page loads, it creates the first link which is associated with an event handler, it fire the first event handler (Getname) but it not firing the second event handler (GetnameDetails)
Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
If ViewState.Item("nameload") IsNot Nothing Then
If ViewState.Item("nameload").ToString = "True" Then
[Code]....
I have a form that is derived from a base class. When the form is created a behavior class is also generated that handles event management, bindings, etc...I create a form instance(FormFoo). When the associated behavior class is created it has a method in it with a signature of: grid_EventA(....) Handles grid.eventA
I want to handle EventA in FormFoo instead of the behavior class so I remove the handler that was generated in the behavior class and add a handler that points to a method in FormFoo. This all works just peachy. The event is properly handled in FormFoo only.
Next I instantiate a modal form(FormBar) via a button click in FormFoo. I then close FormBar. Now we have a problem.When eventA fires it is now handled from the Event handler in FormFoo AND in the behavior class associated with form foo(bad).Is the event handler in the behavior class(grid_EventA(....) Handles grid.eventA) getting resubscribed when the form gets focus again? I don't understand how that event is getting resubscribed.
I figured it out I removed the Handles grid.EventA from the method signature:
grid_EventA(....) Handles grid.eventA
Then I added the handler during initialization of the BehaviorClass using:
AddHandler grid.EventA, AddressOf grid_EventA
Once I did that the problem went away. It appears that when you use MethodName(..) Handles that the event bindings get reset when the control comes back into focus.
In C# I can test for this...
public event EventHandler Trigger;
protected void OnTrigger(EventArgs e)
{
[Code]....
Is there a way to do this in VB.NET? Test for null I mean?
MORE INFO
I forgot to mention. I have classes written in C# but I am writing my unit tests in VB.NET.
I am trying this in the unit test...
If myObject.Trigger IsNot Nothing Then
''#do something
End If
This is causing a compile time error which says ... "Public Event Trigger is an Event and cannot be called directly. Use the RaiseEvent statement to raise an event."
I am trying to convert this code written in C# to VB:[code]This is what I have currently, but it always throws an error when I run it:[code]
View 3 RepliesAt the beginning of a VB .NET function I remove an event handler and add it again at the end of the function because the function's code would trigger those events and I do not want them to trigger for the duration of the function. This usually works, but I have run into a few situations where the event still gets called even though I have already removed it. Sometimes removing it twice at the beginning of the function fixes it, but other times no matter how many times I remove it, it still fires.
Edit:The code is in a Form that has a virtual mode datagridview. I want to run some operations that will trigger the CellValueNeeded event for the datagridview without that event being fired (because it will interfere).
Public Sub DoEventRaisingStuff()
RemoveHandler grid.CellValueNeeded, AddressOf grid_CellValueNeeded
'Do things that would trigger CellValueNeeded
AddHandler grid.CellValueNeeded, AddressOf grid_CellValueNeeded
End Sub
Removing the handler multiple times does not prevent the event from firing, so it doesn't seem to be added multiple times somewhere else by accident.Is there a way to find out what event handlers are active?
I'd like to know how to attach an event handler in VB,There is a C# sample code in this URL that I want to convert to VB (Figure 8)
http://msdn.microsoft.com/msdnmag/issues/06/01/speechinWindowsVista/default.aspx?loc=&fig=true#fig8
I have succesfully converted every lines to VB except those :
[code].....
I have a chart Component that was rendering based on my menu selection(say Sales data, Purchase data), I have two different class to render this, In main form i have a chart control(which was referenced by my appropriate class), When I choose "sales" both sales and purchase chart rendering event handler called, how to solve this?
View 1 RepliesWhy can't I get the clickedItem.SelectedItems.Item(0).Text value?
Dim UserList As New ListView()
AddHandler UserList.MouseDown, AddressOf ToolSearchAD_ListView_Click
UserList.ContextMenuStrip = c_mnuADSearch
[code].....
