I don't understand why I only get 1 Message Box in the following case when I run using (CTRL-F5 - Run Without Debugger) in VS2010:
Public Class Form1
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
' Add the event handler for handling UI thread exceptions to the event.
AddHandler Application.ThreadException, AddressOf ThreadExceptionHandler
[code].....
I've got a VB2008 Form app and I'm trying to handle all my UI exceptions in a single method that handles the Application.ThreadException event. When I build a version and run it, this handler appears to be working fine. However, in debug mode, when an exception occurs the debuggernow halts on the exception and won't progress even if I hit F5. I want it to progress onwards and let the handler do its work. That's what it used to do, though I realize the difference is now there isn't a Catch block anymore. Any way to make the debugger keep going? It's making me nervous thinking perhaps things aren't set up right.
View 1 RepliesI have an Unhandled Exception handler that does something like this[code]...
So it looks like from the "add" that the last person that subscribes to Application.ThreadException is the one who gets it (it's not additive as most event handlers are). I don't want to give up my subscription to this eventhandler no matter what. Can anyone think of a way that I could track when I lose my subscription to the Application.ThreadException so I can steal it back from whoever stole it from me?
I have been trying to reference Application.ThreadException in my application to make an addhandler, but I also am using imports growl.connector which has a growl.connector.application method. When I create my addhandler:AddHandler Application.ThreadException, AddressOf ThreadExceptionHandler
And I get "ThreadExecption is not an event of 'growl.connector.application'"
How do I get a Event Handler to fire from within a nother Event Handler?
View 6 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
[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?
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 RepliesHere is a problem with focus. I have a container(e.g. Panel) which contains some controls. How can I detect the focus event whenever any of the controls in the container has received or lost focus? Do I need to add handler for each control?
example: If all controls in the container have no focus, the container will report as inactive; if one of the controls has focus, the container will report as active.
I designing download manager in vb.net. Which supports various file premium hosts[rs,hotfile].... My need is how to get the download handler of IE. When user navigate the link in IE the download link wil be catch by professional application like(dap, idm).... How to achieve in my application? I meant how to get redirected link?
View 2 RepliesI 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 RepliesWhen adding a handler I want to be sure adding a unique(single) instance of the delegate. [code]...
View 18 RepliesHow I can run handler from one application to another, for example: In application one i have form1 and button. In application two I have also form1 and button. Now how I can run handler for button on form1 in first application from applicaton two?
View 2 RepliesI am trying to add a Handler, but it do not work. what am I missing? I getting this error.
Dim EditingTextBox As New TextBox
Dim Save_Button As New Button
Dim Cancel_Button As New Button
Private Sub Labels_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click
[code]....
I'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.
Is it possible in VB.NET to easily write an event handler that will handle every event that fires? I'm wondering if one could make a logging system using something like this.I'm wanting to do something like (in pseudocode):
Public Sub eventHandledEvent(ByVal sender As Object, ByVal e As EventArgs)
File.Write(sender.EventName)
End Sub
I realize it would be slow, but it wouldn't be for a production system, only as a development tool.
I am trying to upload images using generic handler as shown below and I have a normal aspx page where I am showing all the uploaded images after uploading.Everything is working fine.
CODE:
Now I want to add a session variable by generating a random string and add the uploaded images to the newly created random string.
1.I have seen this Question on SO to use System.Web.SessionState.IRequiresSessionState for sessions and how do I create a folder with that and add my images to that folder after doing that how do I access this session variable in my normal aspx page.
2.(Or) the better way is create session variable in aspx page and pass that to handler?If so how can I do that?
3 .I am trying to find the control from my handler.Is that possible?If anyone knows how to get this then also my problem will get resolved so that I am trying to create a session from m aspx page.
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]....
So i had a some objects on my project like a few textboxs and buttons, which all had code tied to. For example text1 button1. I delete the two objects (not code) from the project and then paste a text1 and button1 (same exact names) back into the form. now when you click button1 or text1 you get
"Private Sub Button7_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click"
rather than the code all ready in the project for button7. The reason im doing this weird situation was because i goofed some of the object settings and was copy and pasting the old objects from a backup version.
How I can run handler from one application to another, for example:
In application one I have form1 and button.
In application two I have also form1 and button.
Now how I can run handler for button on form1 in first application from application two?
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 RepliesI want to create a property handler in .NET. I have already implemented the IInitializeWithFile, IPropertyStore and IPropertyStoreCapabilities classes but I don't know how to implement their functions to create custom properties and display data.[url]...
View 1 RepliesIn an attempt to learn how to program in VB I thought I would have a go at working through some of the examples in the VB2008 express edition documentation. The following example expects an event handler to exist. I am having difficulty understanding how to declare an event handler.I have lifted the following from the VB2008 express edition documentation.[URL] CONTROLS AT RUN TIME... The Visual Basic 2008 example also assumes that an event handler named TextChangedHandler exists for the first TextBox control. - I NEED TO DO THIS. Private Sub TextBoxes_AddText(ByVal sender As System.Object, ByVal e As System.EventArgs)' Declare a new TextBox.Dim TextBoxB As New TextBox' Set the location below the first TextBoxTextBoxB.Left = TextBoxA.LeftTextBoxB.Top = TextBoxA.Top + 10' Add the TextBox to the form's Controls collection.Me.Controls.Add(TextBoxB)AddHandler TextBoxB.TextChanged, AddressOf TextChangedHandlerEnd SubSo I did something like this ...Private Sub TextChangedHandler(ByVal sender As System.Object, ByVal e As System.EventArgs) _Handles TextBoxA.TextChanged End
View 4 RepliesI have the current code:Public Declare Function FindWindow Lib "user32.dll" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
<DllImport("user32.dll", SetLastError:=True, CharSet:=CharSet.Auto)> _
Private Shared Function SendMessage(ByVal hWnd As HandleRef, ByVal Msg As UInteger, ByVal wParam As IntPtr, ByVal lParam As String) As
[code].....
At 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've been trying to write a utility program that enables you to click a certain number of times and having a specified program open up when that happens. Ex: If I consecutively click 5 times it will open explorer, 6 times will open outlook, ect.I have the entire program writen out, the only things thats stopping its completion is that I can only log clicks that happen ON the form, not on the desktop, or within any window (globally detecting mouse clicks, as opposed to only on the forum
Code:
Private Sub Form1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Click
[code]......