How Do I: 'System.ObjectD isposedExceptio n'

[Brian]

Hello all.

I have a simple application that I was using to test and understand
the System.Timers.T imer and noticed that when I stop the application,
on occasion, it throughs the following exception.

An exception of type 'System.ObjectD isposedExceptio n' occurred in
System.Windows. Forms.dll but was not handled in user code

Additional information: Cannot access a disposed object.

Should I just place the offending line in a Try Catch or set the timer
to nothing in FormClosing. Below is the code, real short.
Public Class formMain
Dim c As New Chronology
Dim WithEvents UpdateTmr As System.Timers.T imer
Dim StartTime As Date
Dim BlockWindowStar t As Date
Dim BlockWindowEnd As Date

Private Sub formMain_Load(B yVal sender As System.Object, ByVal e
As System.EventArg s) Handles MyBase.Load
UpdateTmr = New System.Timers.T imer
UpdateTmr.Inter val = 1000
UpdateTmr.Enabl ed = True
StartTime = DateTime.Now
BlockWindowStar t = StartTime.AddSe conds(10)
BlockWindowEnd = BlockWindowStar t.AddSeconds(10 )

End Sub
Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed
'Exception is thrown
here.<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<
Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
End Sub

Public Delegate Sub delUpdateForm()
Public Sub UpdateForm()
Label1.Text = Now
Dim x As DateTime = DateTime.Now
Dim tsw As TimeSpan = BlockWindowEnd - BlockWindowStar t
Debug.Print("Bl ock Window Value: " & tsw.Ticks)

Dim ts As TimeSpan = DateTime.Now - BlockWindowStar t
Debug.Print(ts. Ticks)
Debug.Print(Dat eTime.Now >= BlockWindowStar t And DateTime.Now
<= BlockWindowEnd)
End Sub
End Class

[kimiraikkonen]

On Apr 14, 8:09 pm, Brian <LineSupp...@gm ail.comwrote:

Hello all.

I have a simple application that I was using to test and understand
the System.Timers.T imer and noticed that when I stop the application,
on occasion, it throughs the following exception.

An exception of type 'System.ObjectD isposedExceptio n' occurred in
System.Windows. Forms.dll but was not handled in user code

Additional information: Cannot access a disposed object.

Should I just place the offending line in a Try Catch or set the timer
to nothing in FormClosing. Below is the code, real short.

Public Class formMain
Dim c As New Chronology
Dim WithEvents UpdateTmr As System.Timers.T imer
Dim StartTime As Date
Dim BlockWindowStar t As Date
Dim BlockWindowEnd As Date

Private Sub formMain_Load(B yVal sender As System.Object, ByVal e
As System.EventArg s) Handles MyBase.Load
UpdateTmr = New System.Timers.T imer
UpdateTmr.Inter val = 1000
UpdateTmr.Enabl ed = True
StartTime = DateTime.Now
BlockWindowStar t = StartTime.AddSe conds(10)
BlockWindowEnd = BlockWindowStar t.AddSeconds(10 )

End Sub

Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed
'Exception is thrown
here.<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<
Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
End Sub

Public Delegate Sub delUpdateForm()
Public Sub UpdateForm()
Label1.Text = Now
Dim x As DateTime = DateTime.Now
Dim tsw As TimeSpan = BlockWindowEnd - BlockWindowStar t
Debug.Print("Bl ock Window Value: " & tsw.Ticks)

Dim ts As TimeSpan = DateTime.Now - BlockWindowStar t
Debug.Print(ts. Ticks)
Debug.Print(Dat eTime.Now >= BlockWindowStar t And DateTime.Now
<= BlockWindowEnd)

End Sub
End Class

Brian,
I tried your code and works fine if you remove the unused class called
"Chronology " at the top of your codepage, because i get "Chronology
not defined" error which you might referenced to an exernal library.

So, i noticed that your code presents the current date and time in the
progress of being updated.

Would you mind using this instead of the code you have if you're still
having difficulty?

Place a timer control named timer1 then paste the following code:

' -------------- Begin ------------

Public Class Form1

Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load

Timer1.Enabled = True

End Sub

Private Sub Timer1_Tick(ByV al sender As System.Object, ByVal e As
System.EventArg s) Handles Timer1.Tick

Label1.Text = DateString + " " + TimeString

End Sub

End Class

' ------------- End ----------

As i noticed that does pretty same job with your code.

Hope this helps,

Onur Güzel

[kimiraikkonen]

On Apr 14, 8:25 pm, kimiraikkonen <kimiraikkone.. [e-mail] e:

On Apr 14, 8:09 pm, Brian <LineSupp...@gm ail.comwrote:

Hello all.

I have a simple application that I was using to test and understand
the System.Timers.T imer and noticed that when I stop the application,
on occasion, it throughs the following exception.

An exception of type 'System.ObjectD isposedExceptio n' occurred in
System.Windows. Forms.dll but was not handled in user code

Additional information: Cannot access a disposed object.

Should I just place the offending line in a Try Catch or set the timer
to nothing in FormClosing. Below is the code, real short.

Public Class formMain
Dim c As New Chronology
Dim WithEvents UpdateTmr As System.Timers.T imer
Dim StartTime As Date
Dim BlockWindowStar t As Date
Dim BlockWindowEnd As Date

Private Sub formMain_Load(B yVal sender As System.Object, ByVal e
As System.EventArg s) Handles MyBase.Load
UpdateTmr = New System.Timers.T imer
UpdateTmr.Inter val = 1000
UpdateTmr.Enabl ed = True
StartTime = DateTime.Now
BlockWindowStar t = StartTime.AddSe conds(10)
BlockWindowEnd = BlockWindowStar t.AddSeconds(10 )

End Sub

Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed
'Exception is thrown
here.<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<
Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
End Sub

Public Delegate Sub delUpdateForm()
Public Sub UpdateForm()
Label1.Text = Now
Dim x As DateTime = DateTime.Now
Dim tsw As TimeSpan = BlockWindowEnd - BlockWindowStar t
Debug.Print("Bl ock Window Value: " & tsw.Ticks)

Dim ts As TimeSpan = DateTime.Now - BlockWindowStar t
Debug.Print(ts. Ticks)
Debug.Print(Dat eTime.Now >= BlockWindowStar t And DateTime.Now
<= BlockWindowEnd)

End Sub
End Class

Brian,
I tried your code and works fine if you remove the unused class called
"Chronology " at the top of your codepage, because i get "Chronology
not defined" error which you might referenced to an exernal library.

So, i noticed that your code presents the current date and time in the
progress of being updated.

Would you mind using this instead of the code you have if you're still
having difficulty?

Place a timer control named timer1 then paste the following code:

' -------------- Begin ------------

Public Class Form1

Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load

Timer1.Enabled = True

End Sub

Private Sub Timer1_Tick(ByV al sender As System.Object, ByVal e As
System.EventArg s) Handles Timer1.Tick

Label1.Text = DateString + " " + TimeString

End Sub

End Class

' ------------- End ----------

As i noticed that does pretty same job with your code.

Hope this helps,

Onur Güzel

Note, don't forget to set timer's interval to 1000 miliseconds.

[Brian]

On Apr 14, 1:28*pm, kimiraikkonen <kimiraikkone.. [e-mail] e:

On Apr 14, 8:25 pm, kimiraikkonen <kimiraikkone.. [e-mail] e:

On Apr 14, 8:09 pm, Brian <LineSupp...@gm ail.comwrote:

Hello all.

I have a simple application that I was using to test and understand
the System.Timers.T imer and noticed that when I stop the application,
on occasion, it throughs the following exception.

An exception of type 'System.ObjectD isposedExceptio n' occurred in
System.Windows. Forms.dll but was not handled in user code

Additional information: Cannot access a disposed object.

Should I just place the offending line in a Try Catch or set the timer
to nothing in FormClosing. Below is the code, real short.

Public Class formMain
* * Dim c As New Chronology
* * Dim WithEvents UpdateTmr As System.Timers.T imer
* * Dim StartTime As Date
* * Dim BlockWindowStar t As Date
* * Dim BlockWindowEnd As Date

* * Private Sub formMain_Load(B yVal sender As System.Object, ByVale
As System.EventArg s) Handles MyBase.Load
* * * * UpdateTmr = New System.Timers.T imer
* * * * UpdateTmr.Inter val = 1000
* * * * UpdateTmr.Enabl ed = True
* * * * StartTime = DateTime.Now
* * * * BlockWindowStar t = StartTime.AddSe conds(10)
* * * * BlockWindowEnd = BlockWindowStar t.AddSeconds(10 )

* * End Sub

* * Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed
'Exception is thrown
here.<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<
* * * * Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
* * End Sub

* * Public Delegate Sub delUpdateForm()
* * Public Sub UpdateForm()
* * * * Label1.Text = Now
* * * * Dim x As DateTime = DateTime.Now
* * * * Dim tsw As TimeSpan = BlockWindowEnd - BlockWindowStar t
* * * * Debug.Print("Bl ock Window Value: " & tsw.Ticks)

* * * * Dim ts As TimeSpan = DateTime.Now - BlockWindowStar t
* * * * Debug.Print(ts. Ticks)
* * * * Debug.Print(Dat eTime.Now >= BlockWindowStar t And DateTime.Now
<= BlockWindowEnd)

* * End Sub
End Class

Brian,
I tried your code and works fine if you remove the unused class called
"Chronology " at the top of your codepage, because i get "Chronology
not defined" error which you might referenced to an exernal library.

So, i noticed that your code presents the current date and time in the
progress of being updated.

Would you mind using this instead of the code you have if you're still
having difficulty?

Place a timer control named timer1 then paste the following code:

' -------------- Begin ------------

Public Class Form1

Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load

Timer1.Enabled = True

End Sub

Private Sub Timer1_Tick(ByV al sender As System.Object, ByVal e As
System.EventArg s) Handles Timer1.Tick

Label1.Text = DateString + " " + TimeString

End Sub

End Class

' ------------- End ----------

As i noticed that does pretty same job with your code.

Hope this helps,

Onur Güzel

Note, don't forget to set timer's interval to 1000 miliseconds.- Hide quoted text -

- Show quoted text -

Sorry, the Chronology class is empty at the moment, I intended to put
all of the code dealing with dates or times in this class. Just didn't
get that far before the exception happened.

Thanks for the suggestions though. I would prefer to stay away from
the Windows Forms Timer because eventually I want this to be a class.
But just to clarify, the exception is not thrown each time I close the
app, just occasionaly. I believe that because the Timer is running in
it's own thread, the call back can occur as the form is closing, after
the form has been disposed, so I get the error.

Thanks

[Stephany Young]

Two ways to deal with it immediately to mind:

1.
Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed

Try
Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
Catch _ex As ObjectDisposedE xception
' Take no action
Catch _ex As Exception
' Deal with this situation
End Try
End Sub

2.
Handle the FormClosing event for the form and, in it:

UpdateTmr.Enabl ed = False

Using the first example means that you are dealing with the exception.

Using the second example means that you are stopping the exception from
occuring.
"Brian" <Li*********@gm ail.comwrote in message
news:81******** *************** ***********@m71 g2000hse.google groups.com...

Hello all.

I have a simple application that I was using to test and understand
the System.Timers.T imer and noticed that when I stop the application,
on occasion, it throughs the following exception.

An exception of type 'System.ObjectD isposedExceptio n' occurred in
System.Windows. Forms.dll but was not handled in user code

Additional information: Cannot access a disposed object.

Should I just place the offending line in a Try Catch or set the timer
to nothing in FormClosing. Below is the code, real short.
Public Class formMain
Dim c As New Chronology
Dim WithEvents UpdateTmr As System.Timers.T imer
Dim StartTime As Date
Dim BlockWindowStar t As Date
Dim BlockWindowEnd As Date

Private Sub formMain_Load(B yVal sender As System.Object, ByVal e
As System.EventArg s) Handles MyBase.Load
UpdateTmr = New System.Timers.T imer
UpdateTmr.Inter val = 1000
UpdateTmr.Enabl ed = True
StartTime = DateTime.Now
BlockWindowStar t = StartTime.AddSe conds(10)
BlockWindowEnd = BlockWindowStar t.AddSeconds(10 )

End Sub
Private Sub UpdateTmr_Elaps ed(ByVal sender As Object, ByVal e As
System.Timers.E lapsedEventArgs ) Handles UpdateTmr.Elaps ed
'Exception is thrown
here.<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<<<<<<<<<< <<<<<<
Me.Invoke(New delUpdateForm(A ddressOf UpdateForm))
End Sub

Public Delegate Sub delUpdateForm()
Public Sub UpdateForm()
Label1.Text = Now
Dim x As DateTime = DateTime.Now
Dim tsw As TimeSpan = BlockWindowEnd - BlockWindowStar t
Debug.Print("Bl ock Window Value: " & tsw.Ticks)

Dim ts As TimeSpan = DateTime.Now - BlockWindowStar t
Debug.Print(ts. Ticks)
Debug.Print(Dat eTime.Now >= BlockWindowStar t And DateTime.Now
<= BlockWindowEnd)
End Sub
End Class

[Cor Ligthert[MVP]]

Brian-,

Why not simple ?

\\\
Private WithEvents UpdateTmr As New System.Timers.T imer
///

-Cor