Catching Property Changed?
Feb 18, 2012Private _pages As New List(Of Panel)
Public ReadOnly Property pages() As List(Of Panel)
Get
[code].....
ADVERTISEMENT
Wpf - Catching Which Cell Changed In Editable Datagrid?
Mar 6, 2012I have an editable DataGrid in a VB WPF application. The DataGrid itself has its SourceUpdated property set to my event handler. 2 of the columns in the grid are editable and have their NotifyOnSourceUpdated flag in the Binding set to True. The event is firing properly, but I can't seem to figure out the best way to determine what has changed. The 2 columns depend on each other in that one of them is an item quantity and the other is a case quantity. If the user changes one of them I want to re-compute the other value and update the grid as well as the binding source. I'm sure there are a number of ways to handle this, but I'm curious what is the best way. I could listen for change event on the datagrid, see what changed, set some variables, and then use those in the SourceUpdated event, but that doesn't seem elegant.
View 1 RepliesC# - Why Is Attached Property Property Changed Event Only Firing One Time
Nov 27, 2010I have a listbox binded to a list of objects. For each list item I wanted to have a rectangle whose fill color is determined by a few properties of the binded object. So I did the following:
Made sure INotifyPropertyChanged was implemented on my object.Created a class to expose the properties I am interested in as attached properties.Binded the properties of the object to the attached properties of the rectangle Created a style that uses triggers to set the rectangle fill based on attached properties.
This works, but only the first time the property of the object changes. After that, the attached properties do not seem to be receiving notification when the data object's property changes. I have double checked and my data object is raising the INotifyPropertyChanged event.
<Rectangle Style="{StaticResource RecordStateRectangleStyle}"
Width="10" Height="10" Stroke="Black"
local:RecordAttachment.RecordState="{Binding Path=RecordState}"
local:RecordAttachment.IsDeleted="{Binding Path=IsDeleted}" />
[code]....
How To Get DataBindings To Be Two Way When Property Changed
Nov 11, 2010I'm having trouble using DataBindings in a Windows Form / User Control. For example: Create a windows form, place a single text-box on it & place two buttons on it. The code behind the form is:
Imports System.ComponentModel
Public Class Form1
Implements System.ComponentModel.INotifyPropertyChanged
Public Event PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) Implements System.ComponentModel.INotifyPropertyChanged.PropertyChanged
[Code] .....
If you type something into the text box & press Button1, you'll get a message box with the text of the property in it. If, however, you press Button2 (which sets the property in code) and then press Button1 again, you'll see that while the property was indeed set in the code, the text box doesn't reflect the change.
Updated the code to provide the implementation of INotifyPropertyChanged. This now works as desired.
Variable/property Changed Event In .net?
Jan 3, 2010How can I make an event that is raised when a variable or property is changed (or can I just put the code I would put in an event in the Set section of a property?
View 5 RepliesGet Notified When List Of Custom Type Property Changed?
Mar 2, 2011I have a class and one of the properties is a list of a custom class. The caller gets the list and is adding instances of class to the list. How do I get notified that the list has been updated?
Private _list as List(of MyType)
Private _totalField1 as Integer
Public Property MyTypeList As List(Of MyType)
Get
Return _list
End Get
Set(ByVal value As List(Of MyType))
_list= value
_totalField1 = _list.Sum(Function(x) x.Field1)
End Set
End Property
What I'm trying to do is every time a MyType object is added to the list keep a running total of Field1, but adding to the list doesn't use the setter. How can I know when the list has been added or changed?
Sorting - Change Rank Property Of MyClass By Last Changed Item In OXT
Feb 22, 2011dim oXT As New Generic.SortedDictionary(Of String, MyClass)
[Code]...
Handle An Object's Object Property Changed Event In .NET Windows Forms?
Jun 7, 2012I know how to handle a single objects property changed event very easily. I want to handle a objects property changed event that is part of another object.
Given Object:
[ObjectY = Y]
+ Public WithEvents X As ObjectX
I would like to do something like:
Private Sub XPropertyChanged() Handles Y.X.PropertyChanged
Right now I need to create a object that equals the object inside that object and then handle this variable pointers property changed, but that is just annoying.
VB 2008 .suo File Needs To Be Changed/recreated Because A Path Has Changed. All Other Files Are OK
May 5, 2012I changed my Username on my computer from i.e. "xxxxxx x xxxxx" to "Dennis"
VB 2008 during a compile gave me the following error: Error reading icon 'C:Usersxxxxxx x xxxxxAppDataRoamingMicrosoftVBExpress9.0VSProjectApplication.ico' -- The system cannot find the path specified.
The file "VSProjectApplication.ico" is in 'C:UsersDennisAppDataRoamingMicrosoftVBExpress9.0'
Somewhere in the VB2008 "configuration" files I believe that I need to manually change the old path to the new path.
I found the old path in the ".suo" file. The ".suo" file is not a text file. How can I edit the .suo file, save it so that it will work?
Saving Changed Data Before DataViewGrid Selection (Row) Changed?
Jan 20, 2010on my Form I have a DataViewGrid and some textboxes with a save button (they are filled with additional data of the selected row).Save is disabled first, when I change something in the textboxes the save button is enabled.When the user changes a gow in the grid, I want to ask before changing the grid row, if he wants to save (if the button is enabled).I am using RowEnter but this is too late, then the selected row already changed (and my textboxes already got new data)...What event can I use to ask if I should save stuff before the user changes a row?Something like BeforeRowChanging with a chance to cancel changing the row?
View 2 RepliesAsp.net - Catching An Inner Exception - But Only If There Is One
Mar 14, 2011I am trying to catch an exception but occasionally get an inner exception. I want to output both into a label. I often get Object reference not set to instance of an object if there is no inner exception.
Catch ex As Exception
exError = ex.Message.ToString
If Not ex.InnerException.Message Is Nothing Then
[Code]....
Catching NullReferenceException?
Apr 5, 2011When I debug a program my IDE simply does not catch System.NullReferenceException - execution continues as if there were nothing wrong.Moreover, when I go to the menu Debug/Exceptions System.NullReferenceException is not even in the list(Common Language Runtime Exceptions).
I manually add it (there is the Add button) and I put a checkmark in the 'Thrown' and 'User unhandled' column - now IDE catches it, but after I re-load the project the situation re-appears - and NullReferenceException is not on the list again. What may be wrong?
Update:No, when I step through the code the execution does not continue but exits the current block of code (sub or function). There were no Try...Catch blocks and there is a message: A System.NullReferenceException occured in MSCorlib.dll... But why doesn't the debugger stop at this line?
Asp.net - Catch Block Not Catching?
Aug 8, 2011I have a simple function which tries to get a value from an Obout grid filter column, and if the value is empty, ignores it and moves on. For some reason this code ignore my catch block and always shows a System.FormatException when the input string is empty More bizarre, if I use visual studio's debugger and set a breakpoint on that line, the catch block functions normally (after I continue from that line). I have already confirmed that my Debug | Exceptions | CLR are not set to catch when thrown. I have also confirmed this same behavior in the production version.
[Code]...
Catching A Ghost Error
May 8, 2009I have 5 errors that come up every time I run my project They are all "A first chance exception of type 'System.ArgumentException' occurred in System.Drawing.dll"
I have try catch blocks around every piece of code I have written, and it does not seem to catch them, so I opted to catch the appdomain.UnHandledException.
That does not seem to catch them either If I step through the code line by line (several hundred lines so I hold down f8) it does not make the error...
Only when I run full speed.
I can only figure that I am accessing something maybe before an object is completely drawn, however how in the heck would anyone suggest I go about finding it, and why will my global event handler not catch them?
Catching Error In BackgroundWorker?
Dec 22, 2009I am using BackgroundWorker to connect asynchronously to a database. Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]...
While my connection is being opened, I have a "Loading" animation show in a lblCalibration. Once it's connected, the animation stops successfully and shows the calibrated record that I am fetching from my db.
However, if there is an error while connecting to my db for any reason, it does not work. My app freezes. The reason is because I am trying to make a cross-thread call while trying to Catch the error in the DoWork event.[URL]..
but still cannot seem to make any progress. Does anyone have any tips or advice on how to properly catch the error and still run BackgroundWorker?
Catching Exceptions In Soapclient?
Feb 24, 2012Take the TripPriceService.wsdl from this link Add a service reference(ServiceReference1) to a windows application, by giving the wsdl from the mentioned wsdl file saved in local folder. My question has two parts
1) Is the below fault message a valid soap fault as per the wsdl(TripPriceServiceException)?
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:trip="http://trip.price.service">
<soapenv:Header/>
<soapenv:Body>
[code]....
2)Now How to handle and catch the detail tag, when the response is a soap:fault?
Imports windowsapp1.ServiceReference1
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim obj As New ServiceReference1.TripPriceServiceFacadeClient
[code]....
The line obj.getTripPrice, invokes the service. However will it throw an exception if the response is a soap fault(of type TripPriceServiceException)? How to handle such cases, do we need to use ServiceReference1.TripPriceServiceException? We are in a need to handle such faults in our webservice client.
Catching Raised Events?
Apr 5, 2011I have read the documentation on RaiseEvent and Even but still confused. I am using a class that i call that performs a task on a thread.
vb
Public Property MyVar As String
Public Sub MuSub()
[code]....
Loop Not Catching All Values?
Sep 16, 2009'SHEETS For Each ctrl As Control In Me.Controls What am I doing wrong here? When I put in manual text after the line return it fill in but as is it doesn't pick up all the checkboxes under HEADINGS. It does create all the sheets under SHEETS.
Code:
If (TypeOf ctrl Is CheckBox AndAlso CType(ctrl, CheckBox).Checked) AndAlso CType(ctrl, CheckBox).Name.Contains("Sheet") Then
wb.Worksheets("Template").copy(after:=sheet)
[Code]....
VS 2008 Catching WMessages?
Apr 1, 2010I'm not even sure if that's what I want.But, here's my question. I have written a small program to automate the running of some files. These files have the potential to give an error in the form of a MessageBox which will halt the whole process. Is there a way to detect if that window pops up so that I can kill the process so the next file can run.
Also, if I can get the location of this MessageBox, is it possible to get text out of it so that maybe I can email myself the error so that the processes can keep running but I cango to that file and fix it.
.net - Why Isn't The Try/catch Catching The Access Violation
Apr 25, 2012I put a try/catch block around a bit of code that occasionaly throws an expected exception, but rather than catching it and displaying the message box, it stops the debugger and alerts me that the exception is unhandled.How do I handle this exception so my code doesn't stop when the exception occurs?
Friend myDevInfo As New devInfo
''' <summary>
''' Closes the device handle obtained with CreateFile and frees resources.
[code]....
ApplicationEvents Not Catching Un-handled Exceptions
Feb 5, 2011I have a VB.NET application (VS2010, .NET 4.0) that seems to throw an exception under some unknown conditions after a number of hours. In addition to the main thread, there are additional threads running. In reading this link: [URL] it seems like this would be a big help in trapping this exception. I have what are probably some very basic questions:
1. I assume ErrorHandlerForm() in the example refers to the main form of the application, setup.vb in my case. Therefore the last line in the example should be:
[Code]...
I would have expected to to replace ErrorHandlerForm.Form1_UIThreadException with find a setup event such as Setup_UIThreadException but there doesn't appear to be sucn an event.
ApplicationEvents.vb Not Catching Unhandled Exceptions?
May 5, 2011While I understand ApplicationEvents.vb won't catch exceptions in another thread, is there any reason why it shouldn't catch exceptions in the UI thread? From time to time I get exceptions that simply crash the program, even though an exception handler is defined as follows:
Private Sub MyApplication_UnhandledException(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.ApplicationServices.UnhandledExceptionEventArgs) Handles Me.UnhandledException
[code].....
Asp.net - IE Not Catching Enter Key For Form Submission?
Jun 30, 2011I have a simple form with one text box that pass data to SQL and I want it to submit when the user hits the enter key.
In Firefox, this works great. The user puts a number hits enter gets back the results.
However in IE 8 and IE 9 this is not working.
<form id="form1" runat="server" accept="cmdclick"
style="background-position: center; background-image: url('BG.gif'); background-repeat: no-repeat;">
[Code]....
I am not sure what would cause this. I see a lot of people using JavaScript to go around the problem however I do not know how to write JavaScript code.
How can this be done (preferably without JavaScript)?
Catching Application Crash Events
May 9, 2012I made a application in VB.Net. But some users face crash upon startup. That is "A problem caused this program from working correctly" with just one button "Close the program". Since there are lot of things happening when the app loads
View 1 RepliesCatching Events In ArrayList Of Objects
Jul 22, 2009I have an ArrayList that is populated with Objects. These Objects raise events at certain times. How can I capture these events from the ArrayList? i.e.
I want something like this:
Public Sub MyRaisedEvent(ByVal obj as MyObject) Handles MyArrayList.MyEvent
End Sub
Catching Exception / Logging And Rethrowing?
Nov 10, 2010I have a method as follows:
Public Sub Send()
Dim caughtException As Exception = Nothing
Try
//Attempt action.
Catch ex As Exception //Custom exceptions which can be thrown all inherit from Exception.
//Instantiate error object to be logged.
caughtException = ex
End Try
//Log action and if there is an error log this too.
If caughtException IsNot Nothing Then Throw caughtException
End Sub
It is essential that I log the error for reports, which after research, rethrowing the exception is the right thing to do. What I am concerned about is preservation of stack information. In order to keep the code DRY I am logging the action in one place - after the exception has been caught. This functionality is ultimately exposed via WCF.
Catching File Loading Exceptions?
Mar 9, 2011How do i catch an exception for the following piece of code?
If File.Exists(Path)Then
m_TempTable.ReadXml(Path,XmlReadMode.ReadSchema)
I deliberately deleted some code from the xml file to replicate a corrupt file but cannot catch the exception before the program trips up. I want to be able to notify the user there is a corrupt file and get them to re-install it.I have tried trying and catching but the debugger always stops with an XmlSchemaException at - m_TempTable.ReadXml(Path,XmlReadMode.ReadSchema)
The xml file is static information that needs no changing or saving. Would another way of storing this info be better?
Catching ThreadingException In .NET When Sub Main Is Not Accessible?
Mar 14, 2011I have a VB.NET winforms solution, and would like to add the standard application exception handlers - Application.ThreadException and AppDomain.CurrentDomain.UnhandledException.I have the following code from MSDN
' Starts the application. '
<SecurityPermission(SecurityAction.Demand, Flags:=SecurityPermissionFlag.ControlAppDomain)> _
Public Shared Sub Main()
' Add the event handler for handling UI thread exceptions to the event. '
[code]....
How can I do it in VB.NET when I have no acces to the Sub Main() method?Is the case when "Enable Application Framework" of my solution properties is enabled (Sub Main is hidden)...
Clearing Labels After Catching An Error?
Apr 13, 2011I run a program multiplying decimals with integers. If a user enters a non 0 number etc. the try catch works its charm. i added some lines to clear the text boxes and that works fine but
lblReva.text = ""
does not clear the labels where the answers are displayed, on the contrary it displays the correct value calculated and enters a 0 for the erroneous entry. I would like to clear all the labels and text boxes(except the instruction and assingment labels)so the form is clean once more so the user can try to be "more on" target next time.
Try
decReva = CDec(txtBoxa.Text)
decRevb = CDec(txtBoxb.Text)
[code]....
Not integers but constants declared as decimals but that is immaterial here. "Doh"
How To Improve Performance Of App By Error Catching
Mar 7, 2009I'm trying to improve my app with some error catching. I have a module that downloads a file from the Internet to a local folder. At the moment, if the local folder doesn't exist, it just crashes here:
strLocalFile = New FileStream(pPath, FileMode.Create, FileAccess.Write, FileShare.None)
with error:
System.IO.DirectoryNotFoundException was unhandled
Message="Could not find a part of the path 'C:Documents and SettingsSimonDesktop estdownload.zip'."
Source="mscorlib"
How can I do something with that error and stop my app from crashing? Ideally, have a messagebox show saying 'directory not found' or similar.