I never used Public Event, but now I have this line:
Code:
This SHOULD be a "trigger" when something in the event log happens.
Now I have 2 questions:
How do I work with public event? In other words, if I write something like this:
Code:
Is it right?
Last question:
Is there any other way to check event log? I found this: [url]
But is a service, I'm writing an application.
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]....
How do I get a Event Handler to fire from within a nother Event Handler?
View 6 Repliesremove 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'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?
[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?
what is the error in the bleow: 'Public Event OnFilterAdded()' is an event, and cannot be called directly. Use a 'RaiseEvent' statement to raise an event. Note: the error line is italic underline
Imports System
Imports System.Collections
Imports System.Configuration
[Code].....
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].....
I have a VB6 app that works correctly in win7.
I downloaded and installed VS2010 yesterday, and converted the app to VB2010.
The app works correctly except for one problem. I have a label array which has two event handlers defined, one for a double click and one for mouse down.
A double click is ignored and the mouse down event is raised. It shows the left button was clicked once.
If I comment out the mouse down handler, the double click event is raised and it shows left button was clicked twice.
What i want to accomplish is allow a user to double click an array element on the screen which then saves the number associated with that element and then click somewhere else to copy the data or alternatively, drag and drop the element to the new location.
The drag operation on the source element always triggers a mouse down, but so does the first of the two clicks in a double click.
It seems that none of the other newer events are raised, eg GiveFeedbackEvent, QueryContinueDrag, DragOver, etc.
So, how do I trap a double click and a drag start without using the mousedown event for the dragstart?
Is there a method for doing this in VB.NET. I have what I need, but in C#, I have no idea on how to do this with VB.NET.
[code]...
I converted some code from c# to vb, I have the following error:-
m_axCalendar.DoRetrieveDayEvents += New AxXtremeCalendarControl._DCalendarControlEvents_DoRetrieveDayEventsEventHandler(m_axCalendar_DoRetrieveDayEvents)
Red Error = Error1'Public Event DoRetrieveDayEvents(sender As Object, e As AxXtremeCalendarControl._DCalendarControlEvents_DoRetrieveDayEventsEvent)' is an event, and cannot be called directly. Use a
[code]....
I can get rid of Blue error by changing it to : AddressOf m_axCalendar_DoRetrieveDayEvents Not sure how to fix red error?
I want to handle the event "Smallincrement in vb.net 2005 " I am studying through the book BlackBook of VB.nET 2003.
View 1 RepliesWhile being in a base class, I want to remove a base class's object's event that is bound to a function in the child class. A little more detail is, there is a grid control declared in the base class, this grid has a rowselected event which the child class catches. Now staying in the base class I have the access to the grid control object and I want to remove the event handler that is catching its rowselected event and instead bind it to my own eventhandler (inside the base class).
I have been trying this code, its just a simulation of the original code so that things remain simple:
Imports System
Imports System.Reflection
Module Module1
[Code].....
I have a two windows forms classes, a base class and a derived class. The base class has an event handler which handles ValueChanged on some component. I have also written a different event handler for the same event on the derived class.
When I create an instance of the derived class and fire the event, I find that both event handlers run (the base class one and then the derived class one). But I want only the handler in the derived class to run.
Edit: Here is what the code looks like (can't post the actual code):
Public Class BaseForm
Inherits System.Windows.Forms.UserControl
(Windows Form Designer Generated Code)
[Code].....
In Shared add-in the following event handler code for add-in start up is as follows:
Public Sub OnStartupComplete(ByRef custom As System.Array) _
Implements Extensibility.IDTExtensibility2.OnStartupComplete
End Sub
[code].....
AM trying trap specific events for some controls on a form. i tried this, but its not fireing the events
[Code]...
EDIT I found out that am placing the control in multiple controls, on the form is a panel, inside the panel is different groupbox, these group boxes have the controls am trying to trap their events
I have a page that contains dynamically generated Dropdown List controls and I want thant the dynamic dropdown list perform an AutoPostback to fill some other field using the value selected.[code]Control is correctly filled and rendered on ASP page but, after selecting a value, the page is reloaded (AutoPostBack is called) but the control is not diplayed and the sub is not called. I put a breakpoint into the ChangeValue sub but anything happens.I read on some post that handler for the first DropDownList is not necessary but, how is it possible to tell DropDownList to call my sub after changevalue?
View 1 Repliesi struggling to pass two parameter to an event handler basically when the page is load it dynamically create some control lable, textfield, and linkbutton when i click on the link button it fire an event handler, here is my problem i want to pass first the Product ID and quantity, the product id is fetch from the database passit thorugh an object where as the quantity it enter by the user first part of the code it connect to database loop through and display all record on the page dynamcally
[Code]....