Raise Event In One Class And Handle The Event In Another Class?
Dec 27, 2010Is it possible to raise event in one class and handle the event in another class? If so, how?
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Handle An Event Raised In Class Inside Own Class?
Apr 14, 2009I have a "partial" class in VB.NET. Half of it is auto generated by a code generation tool. That half implements INotifyPropertyChanged, so any properties in that part of the partial class raise the PropertyChanged event.In my "custom" part of the class, I declare another property that depends on one of the properties in the auto-generated side. Therefore, when that auto-generated property changes, I also want to raise a PropertyChanged event on my custom property that depends on it.
If I go into the generated part of the class and raise the event there, that will get overwritten if I ever re-generate that part, so I don't want to do that. I would rather add an event handler in my side of the partial class that checks if the generated property changed, and if so, raise another event for my custom property.
[Code]...
I'm assuming it's because normally you'd use the WithEvents keyword to tell the compiler that you're subscribing to events from that object. I don't have a clue how to do this inside of the class that's actually raising the event, or if that's even possible.
Raise An Event From A Class?
Mar 11, 2009I'm trying to raise an event from a class. It looks ok but it did not raise the event as expected...?
Steps
1 - Load the form2
2 - Boutton1 call the form1 and load the class animation
3 - Class animation raise the event for the form1
Here is the code !
Public Class Form1
Private WithEvents AnimationTextChange As Animation
Public Sub mdiMainEvent_StatusTextChange(ByVal _text As String) Handles
[Code]....
Raise Event From Sub Class?
Sep 6, 2009I have 2 classes one main class called Mygrid and another class inside it called TLBoxEditingControl which inherits a textbox into grid cell.Also I have added one Listbox called LstBox to the usercontrol MyGrid.
1) Initially its visible is false. How can i make visible true in TLBoxEditingControl class.
2) I have an Event called MyList() in Main Class, how can I raise this event in TLBoxEditingControl class.
Here is the code i use, This is not working please expalin
Public Class MyGrid
Inherits DataGridView
Public Event MyList()
[code]....
I have added this control to a form and added this code
Private Sub MyGrid1_MyList() Handles MyGrid1.MyList
MsgBox("ggg")
End Sub
Here the event is not raising.
Raise An Event From A Custom Class?
Nov 14, 2011I have a Windows Service project designed to monitor an email account and make entries into a SQL Server database when certain emails arrive. This is a rewrite of a similar winforms program that works just fine, except that it requires that the computer be logged into an account and the program started manually, which I can avoid by using it as a service.In the service I maintain a list of logged messages - basically just a string and a timestamp indicating that something has happened. (That list is shared out over a WCF service but I think that's immaterial, at least at the moment.) In my custom class I declare a public event, and elsewhere I raise that event. For some reason, though, the RaiseEvent isn't being run in the service. For example:
[code]...
The problem in this case is that _pc_HandleEvent isn't ever being called. If I duplicate this setup in a regular winform program, everything works like it should. What am I doing wrong? How do I get a service to handle events raised from other classes?
VS 2010 : UserControl MouseEnter/Leave Events Aren't Firing - Cannot Raise Base Event From Derived Class
Feb 18, 2011When i use my UserControl in a project my Mouse Enter & Leave events aren't firing, i assume i fix this with a raiseevents in my usercontrol. However when i try to do this it says something about "cannot raise base event from derived class".
View 7 RepliesAsp.net - Can A Page Raise An Event That The User Control Can Handle
Mar 13, 2009I have done this the other way many times as it makes sense (the page knows about the control as it has been added to the page and can handle the 'child' event)
Is it possible to do it the other way? I think not as the control doesn't know what page it is going to be on
The reason i ask this is that I have a modal popup on the page to ask users to login, and it is only when the user has logged in that I want my user control to go away and execute some code but I am not too sure how to tell the control this has happend?
Use Raise Event To Raise A Programmatically Added Event
Jun 12, 2011i guess the title pretty much states the question but i will give the senario to be more clear. i have a mousemove() event which i add in my program programmatically and i need a way for raising that event (again) programmatically too. raiseEvent control_mousemove() doesn't work as it says that "'control_MouseDown' is not an event of 'main'."
[Code]...
Any Event Built In The Class That Is Fired Automatically When A Class Is Deserialized And Ready To Be Used?
Nov 18, 2010I have a class that is stored after serialization and compression.Is there any event built in the class that is fired automatically when a class is deserialized and ready to be used??
View 1 RepliesRaise Event - Put An Extra Event In - UpdateID And It's Not Firing
Aug 9, 2011I am trying to put an extra event in, UpdateID and it's not firing.
[Code]...
Industrial App: Raise An Event For Something That Doesn't Have An Event?
Sep 15, 2010I want to raise an event for an opto-input state change but not sure if I can. Basically I have 4 opto-inputs on a PCI control card - one of which changes pretty rapidly - that I currently poll with a timer. I'm looking at getting a proper hardware counter for that but the other 3 are production status indicators. I'd prefer it if they alerted the app to a state change though.
Depending on the state of one of the inputs I have to fire a relay which simulates a button push. Having been playing with serial ports and getting a very useful app built for logging production data into a SQL Server DB I want to re-visit a proof-of-concept system I built a few months ago.
Current code - which works fine - but I'd like to change is like this:
Private Sub tmrOptoInput_0_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrOptoInput_0.Tick
'Read OptoInput_1 to Monitor Track State...
Dim aType As Byte ' replace Byte with any other type
[code].....
Having 4 inputs so I need 4 timers, plus another one that polls the database and checks a status flag which triggers the app to start logging. I'd like it to be event driven rather than timer driven if at all possible but I don't know how and there's nothing in the control card docs. Also I can't seem to find anything relevant on the web.
Raise Event In One Form And Handle It In Another Form?
Jul 13, 2009I have two forms, "Customer Information Summary" and "Products Sold". They are shown as separate tabs in a MDI window. When the data in "Products Sold" gets updated, I would like an event to fire from that form which could be handled in the "Customer Information Summary" form.
View 1 RepliesVS 2008 Using More Event Handlers To A Handle The Same Event?
Mar 6, 2011is it allowed to use more than one Sub to handle the same event ? For example , may I have 2 separate subs to handle the Load event of a form ? Will they fight each other ?I have tested it and it seems to work fine , nevertheless I thought I'd ask you . In case you wonder , there is no great deal , I just want to copy the same lines of code in more forms so I am doing it just in favor of the looking aspect .
View 5 RepliesEvent Handling In Another Class?
Dec 1, 2011I have an event defined and firing in class B
Public myEvent()
In class A:
Private WithEvents _b as B
Private Sub hander() Handles _b.myEvent
but, this handler does not get called.
Event Won't Come Through Class Hierarchy
Feb 2, 2010I'm writing a Windows Forms application in VB.Net 2008, .NET Framework 3.5, and I am trying to handle an event created by a class that get's instantiated several times throughout the program. The thing is the events gets fired in the Functions class, but nothing's happening in the main class.I tried to change the called class by instantiating it in the beginning of the main class, by using 'WithEvents testEvent as MTO_Tool.Functions = New Functions' but that also didn't work.
Code:
' The main class:
Public Class MainScreen
WithEvents testEvent As MTO_tool.Functions
Private Sub test() Handles testEvent.SaveChanges
[code]....
Invoke Event Of Class From Another?
Jul 17, 2011I am new to making events and I have read up on them to further my understanding of them, and I have come across a situation that I am stuck at. Currently I have a handful of classes (lets call them a childform) that are all inherited from a class that's a form (lets call it a parentform) with an event called UpdateData(). When these forms are created they are added into a hashtable of ParentForms then added into another form. I call on these forms through a method that returns the form from the hastable. [code]....
View 2 RepliesTrigger An Event From Within Another Class?
Jun 5, 2009In .NET I have a class called Caption. I have another class called Gauge. Within the Gauge class I have a property defined as a Caption.I am trying to figure out how to do thefollowing:When a certain property is changed in my Caption class how do I get it to execute a subroutine in the Gauge class? I am thinking I have to declare an event and AddHandlers to fire it off, but I can't think of how to accomplish this.
View 2 RepliesUsing The Same Name For Event And Method Of Class?
Aug 15, 2011am writing a class that has the same name for events and method, but visual studion won't allow me
The event
public event Close()
the method
Public Sub Close()
End Sub
how can i do this, i don't want to use different names
Add Event To Public NotInheritable Class?
Dec 24, 2009Can i add an event to a Public NotInheritable Class?, in particular i would need to have an event that would listen to property change.System.Web.ClientServices.ConnectivityStatus has a property IsOffline, i would need to know when this property has changed?
Any other way to achieve this?VB.NET to C#[URL]..
Event Handling An Abstract Class?
Jul 6, 2010Basically, I have a custom child form class which has events that will be passed to the parent. In the custom child form, I have a declaration of a "MustInherit" class that inherits the DevExpress User Control Class.
The reason for this, is I have many user controls that derive from this base class, and the child form can have an instance of any one of these controls, and doesnt care which. The only requirement is that the child form can handle the same events from each type of control the same way.
Some watered down code snippets(still pretty long unfortunately):
'''Inherited Class
Public Class ChildControlInheritedClass
[Code].....
Making Variable Class With Event?
Jun 22, 2010I haven't quote grasped this whole "class" concept yet, but I'm working on it. When following the instructions below, the "test" portion of this code: "test.variable". It has an underlined error that says that "test" is not declared. If I remove the "test" word then the ".variable" shows not declared. I'm using Visual Studios 8 if that makes any difference. I have a pre-existing variable in a project that I would like to monitor for changes.
Re: Detect variable change.
Make your variable a class with an event.
Make your class:
VB.NET Syntax (Toggle Plain Text)
Public Class myVar
Private mValue As Integer
Public Event VariableChanged(ByVal mvalue As Integer)
[Code] .....
Pass DataTable Event To Class?
Apr 17, 2012I have a form that contains a DataTable variable (dt) that has a RowChanged event assigned to it. I use a UserControl (DataGridViewFilterAndSorter) to get a subset DataTable from dt. I need dtSubset to have the same event as dt. How can I do this?
In other words, I need to pass the dt event to the DataGridViewFilterAndSorter class and store that event as a class level variable. How can I do this?
Public Class frmCalculatedResults
Private dfs As DataGridViewFilterAndSorter
Private WithEvents dt As DataTable
[Code].....
Serialize A Class Containing A Public Event?
May 14, 2012how can i serialize a class containing a public event + withevents child classes each containing a public event?
View 3 RepliesUse An Event To Trigger A Certain Procedure Of A Class
Jun 4, 2009I read some articles about using events and/or class events, but not a single article realy explainend the true use and benefit of using events in classes, but only how to use them.
As far as I understand, you can use an event to trigger a certain procedure of a class within another class or aspx page, but you can do the same by declaring an object of that class and call de procedure or methods directly. why and when or where we would use an event with addhandler to call a routine from a class and not declare an object of the class and call the desired routine directly.
VS 2010 : Creating An Event For A Class?
Feb 28, 2012I have an application that tests various hardware components for notebooks. One of those components is the keyboard.I have a form that displays a keyboard. In that form's KeyPreview event, I get which key is pressed. If it's the correct key, I disable the visual UI cue and move on to the next key.I'm converting the bulk of the code into a library so that it can be used in other projects more easily. But I'm having a hard time grasping how I would create this event in my library and still allow the same functionality.
View 10 RepliesExecute The New Class From The Form LOAD Event?
Oct 25, 2010I want to develop a program using VS 2010 Pro, VB and .NET 4.0 to run on a Windows standalone computer.The program will be loaded by another program that checks for a text file in a directory.When that file exists, the program I want to develop will be started and it will process the text file.The new program will not have any buttons or dialog boxes, it will simply display the progress of the processing of the text file and then it will simply terminate and exit.
I know I can start the processing by putting code in the LOAD event for the form, but i want to make a new class for all the processing to start from and have the new class perform all of the steps necessary to complete the processing of the text file.Of course this new class will use other classes to do all of the different processing steps.How do I execute that new class from the Form LOAD event?
C# - Respond To Descendent Class PropertyChanged Event?
Mar 10, 2011I have a class, BaseSample, that uses another class, MainData, as one of its fields:
Protected _sampleData As MainData
Public Property SampleData() As MainData
Get
[code]....
MainData in turn has a collection of a class, ProcessData, as a field and ProcessData has a collection of a class, Measurement, as a field. I.e.:
MainData
|- IEnumerable (Of ProcessData)
|- IEnumerable (Of Measurement)
These classes are entities in a LINQ to SQL file. In the Measurement class, I raise the PropertyChanged event when the CrucibleOxidizedMass property changes:
Private Sub OnCrucibleOxidizedMassChanged()
RaiseEvent PropertyChanged(Me, New ComponentModel.PropertyChangedEventArgs("CrucibleOxidizedMass"))
End Sub
In the BaseSample class, I want to respond to the CrucibleOxidizedMass PropertyChanged event in any of the descendent Measurment instances. How would I do this?
Call A Public Class From The Load Event?
Oct 19, 2010I would like to know how to call the "Public Class Test" that I created in my app which creates a directory and subdirectories. Now, how and where do I call or reference that "Public Class Test"?
I am using VS2008 (vb)
Event Raised In Constructor Cannot Be Handled Outside Very Class
Oct 26, 2009I discovered that an event raised (directly on indirectly) in the constructor cannot be handled outside the very class. To prove if that was the actual problem, I wrote a simple exemplary app.
Class with the event:
Namespace Utils
Public Class A
Public Event Test()
Public Sub New()
CallTest()
[Code] .....
The reason of such behavior became quite obvious after writing those pieces, but maybe there is a way to omit it?
Execute Custum Event In Public Class?
Nov 21, 2010I'm using VB NET 2005 I have genereted a public class with one event so declare
Public Event Interupt()
I insert this code where I want to generate the events
RaiseEvent Interupt()
To use this class in other class use this code
Public IClass As New Cl
Public WithEvents Data As Cl
The code for the su of event is this:
Public Sub RsEvent () Handles Data.Interupt
Why doesn't came generatethe RsEvent?I verify in debug with break point that the code raise event is executed
