StreamWriter Problem

kimiraikkonen

Hello,
Here's a very annoying problem that i couldn't make out. The problem
is that: I open a text file using "streamreader" with no problem then
when i save my existing txt file using streamWriter, sometimes it
works very well, but sometimes it doesn't save and overwrite existing
file. (Texbox1.text is main text area.)

The problem doesn't occur sometimes but it really hurts. You click
save button and exit. Sometimes changes have been saved successfully
(re-open and see with Windows Notepad), but sometimes nothing has been
saved. That's really cruel. :-(

Here is streamwriter code:

Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
SaveAsToolStripMenuItem.Click
Dim Save As New SaveFileDialog()
Dim myStreamWriter As System.IO.StreamWriter

Save.Filter = "Plain Text Files (*.txt)|*.txt|All files (*.*)|
*.*"
Save.CheckPathExists = True
Save.Title = "Save"
Save.ShowDialog(Me)
Try
myStreamWriter = System.IO.File.CreateText(Save.FileName)
myStreamWriter.Write(TextBox1.Text)
myStreamWriter.Flush()
Catch ex As Exception
' Do nothing on Exception

End Try

End Sub

What's wrong here? Note that, when the fake-save problem occurs, if i
re-save file with several retries without closing my project, then it
gets saved.

Regards.

kimiraikkonen

On Dec 8, 12:48 am, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
> Hello,
> Here's a very annoying problem that i couldn't make out. The problem
> is that: I open a text file using "streamreader" with no problem then
> when i save my existing txt file using streamWriter, sometimes it
> works very well, but sometimes it doesn't save and overwrite existing
> file. (Texbox1.text is main text area.)
>
> The problem doesn't occur sometimes but it really hurts. You click
> save button and exit. Sometimes changes have been saved successfully
> (re-open and see with Windows Notepad), but sometimes nothing has been
> saved. That's really cruel. :-(
>
> Here is streamwriter code:
>
> Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As
> System.Object, ByVal e As System.EventArgs) Handles
> SaveAsToolStripMenuItem.Click
> Dim Save As New SaveFileDialog()
> Dim myStreamWriter As System.IO.StreamWriter
>
> Save.Filter = "Plain Text Files (*.txt)|*.txt|All files (*.*)|
> *.*"
> Save.CheckPathExists = True
> Save.Title = "Save"
> Save.ShowDialog(Me)
> Try
> myStreamWriter = System.IO.File.CreateText(Save.FileName)
> myStreamWriter.Write(TextBox1.Text)
> myStreamWriter.Flush()
> Catch ex As Exception
> ' Do nothing on Exception
>
> End Try
>
> End Sub
>
> What's wrong here? Note that, when the fake-save problem occurs, if i
> re-save file with several retries without closing my project, then it
> gets saved.
>
> Regards.

Edit: However, i added a catch ex as exception handler and received
the exception as "the file is being used by another process" although
nothing is open except my program.

kimiraikkonen

Edit: However, i added a catch ex as exception handler and received
the exception as "the file is being used by another process" although
nothing is open except my program.

Is it a streamwriter bug? Because nothing is using a text file while
i'm trying to save through my project.

Tom Shelton

On Dec 7, 4:23 pm, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
> Edit: However, i added a catch ex as exception handler and received
> the exception as "the file is being used by another process" although
> nothing is open except my program.
>
> Is it a streamwriter bug? Because nothing is using a text file while
> i'm trying to save through my project.

no, it's not a bug in the streamwriter - it's a bug in your code. and
if your code for loading the file is similar to the saving code, then
i can see why. you are never closing the resource. you need to call
close on the streamwriter (and streamreader) when you are done with
them....

using sr as new streamreader(myfile)
' do stuff
end using

using the using block will ensure that the streamreader is properly
cleand up when the block ends. Basically, it will compile like you
had done something like:

dim sr as streamreader = nothing
try
sr = new streamreader(myfile)
' do stuff
finally
if not isnothing(sr) then
sr.dispose()
end finally

you need to do the same with your streamreader.

--
Tom Shelton

kimiraikkonen

On Dec 8, 1:45 am, Tom Shelton <tom_shel...@comcast.net> wrote:
> On Dec 7, 4:23 pm, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
>
> > Edit: However, i added a catch ex as exception handler and received
> > the exception as "the file is being used by another process" although
> > nothing is open except my program.
>
> > Is it a streamwriter bug? Because nothing is using a text file while
> > i'm trying to save through my project.
>
> no, it's not a bug in the streamwriter - it's a bug in your code. and
> if your code for loading the file is similar to the saving code, then
> i can see why. you are never closing the resource. you need to call
> close on the streamwriter (and streamreader) when you are done with
> them....
>
> using sr as new streamreader(myfile)
> ' do stuff
> end using
>
> using the using block will ensure that the streamreader is properly
> cleand up when the block ends. Basically, it will compile like you
> had done something like:
>
> dim sr as streamreader = nothing
> try
> sr = new streamreader(myfile)
> ' do stuff
> finally
> if not isnothing(sr) then
> sr.dispose()
> end finally
>
> you need to do the same with your streamreader.
>
> --
> Tom Shelton

I was using this before i posted with no help:
Try
......
Catch

Finally
If Not myStreamWriter Is Nothing Then
myStreamWriter.Close()
End If

kimiraikkonen

On Dec 8, 1:45 am, Tom Shelton <tom_shel...@comcast.net> wrote:
> On Dec 7, 4:23 pm, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
>
> > Edit: However, i added a catch ex as exception handler and received
> > the exception as "the file is being used by another process" although
> > nothing is open except my program.
>
> > Is it a streamwriter bug? Because nothing is using a text file while
> > i'm trying to save through my project.
>
> no, it's not a bug in the streamwriter - it's a bug in your code. and
> if your code for loading the file is similar to the saving code, then
> i can see why. you are never closing the resource. you need to call
> close on the streamwriter (and streamreader) when you are done with
> them....
>
> using sr as new streamreader(myfile)
> ' do stuff
> end using
>
> using the using block will ensure that the streamreader is properly
> cleand up when the block ends. Basically, it will compile like you
> had done something like:
>
> dim sr as streamreader = nothing
> try
> sr = new streamreader(myfile)
> ' do stuff
> finally
> if not isnothing(sr) then
> sr.dispose()
> end finally
>
> you need to do the same with your streamreader.
>
> --
> Tom Shelton

I was using this for streamwriter also of streamreader before i posted
with no help:
Try
......
Catch

Finally
If Not myStreamWriter Is Nothing Then
myStreamWriter.Close()
End If

Ryan S. Thiele

Hi,

Are you trying to overwirte a file that already exist? The stream reader may
be trying to open a file that is use, or may be trying to append the data.

When your calling for the write code, try this

Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As _
System.Object, ByVal e As System.EventArgs) Handles
SaveAsToolStripMenuItem.Click
Dim Save As New SaveFileDialog()
Dim myStreamWriter As System.IO.StreamWriter

Save.Filter = "Plain Text Files (*.txt)|*.txt|All files (*.*)|*.*"
Save.CheckPathExists = True
Save.Title = "Save"
' ----- Added Code -----------
If Save.ShowDialog(Me) = DialogResault.OK then
Try
' ---------- Added Code -------------
If File.Exist(Save.Filename) then File.Delete
(Save.FileName)

myStreamWriter = System.IO.File.CreateText(Save.FileName)
myStreamWriter.Write(TextBox1.Text)
myStreamWriter.Flush()
Catch ex As Exception
' Do nothing on Exception
' ---- I would put this code in to see what error is
occuring, if any...
Msgbox(ex.ToString)
End Try
End IF
End Sub


------------
Hope this helps, let me know.

--
Ryan S. Thiele
RT Enterprises
The Power is in your hands now!

kimiraikkonen

On Dec 8, 6:01 am, "Ryan S. Thiele"
<administra...@carriercompanion.com> wrote:
> Hi,
>
> Are you trying to overwirte a file that already exist? The stream reader may
> be trying to open a file that is use, or may be trying to append the data.
>
> When your calling for the write code, try this
>
> Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As _
> System.Object, ByVal e As System.EventArgs) Handles
> SaveAsToolStripMenuItem.Click
> Dim Save As New SaveFileDialog()
> Dim myStreamWriter As System.IO.StreamWriter
>
> Save.Filter = "Plain Text Files (*.txt)|*.txt|All files (*.*)|*.*"
> Save.CheckPathExists = True
> Save.Title = "Save"
> ' ----- Added Code -----------
> If Save.ShowDialog(Me) = DialogResault.OK then
> Try
> ' ---------- Added Code -------------
> If File.Exist(Save.Filename) then File.Delete
> (Save.FileName)
>
> myStreamWriter = System.IO.File.CreateText(Save.FileName)
> myStreamWriter.Write(TextBox1.Text)
> myStreamWriter.Flush()
> Catch ex As Exception
> ' Do nothing on Exception
> ' ---- I would put this code in to see what error is
> occuring, if any...
> Msgbox(ex.ToString)
> End Try
> End IF
> End Sub
>
> ------------
> Hope this helps, let me know.
>
> --
> Ryan S. Thiele
> RT Enterprises
> The Power is in your hands now!

Hi Ryan,
Yes, the problem occurs when i'm trying to overwrite an existing file.

However i re-edited the code you suggested (just correct some typing
errors) as this:

' ----- Added Code -----------
If Save.ShowDialog(Me) = DialogResult.OK Then
Try
' ---------- Added Code -------------
If System.IO.File.Exists(Save.FileName) Then
System.IO.File.Delete(Save.FileName)

myStreamWriter =
System.IO.File.CreateText(Save.FileName)
myStreamWriter.Write(TextBox1.Text)
myStreamWriter.Flush()
Catch ex As Exception
MsgBox(ex.Message)

End Try
End If


But again and again, i receive that the file is being used by another
process when i try to save but not always.

Teemu

Could you use this code:

Dim Save As New SaveFileDialog()
Save.Filter = "Plain Text Files (*.txt)|*.txt|All files (*.*)|*.*"
Save.CheckPathExists = True
Save.Title = "Save"

If Save.ShowDialog(Me) = DialogResult.OK Then
Try
Dim myStreamWriter As System.IO.StreamWriter = New
System.IO.StreamWriter(Save.FileName)
myStreamWriter.Write(TextBox1.Text)
myStreamWriter.Close()
myStreamWriter.Dispose()

Catch ex As Exception

MsgBox(ex.ToString)

End Try
End If

It will overwrite the existing file if it exists, otherwise it creates a new
file.

-Teemu

Tom Shelton

On Dec 7, 5:01 pm, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
> On Dec 8, 1:45 am, Tom Shelton <tom_shel...@comcast.net> wrote:
>
>
>
>
>
> > On Dec 7, 4:23 pm, kimiraikkonen <kimiraikkone...@gmail.com> wrote:
>
> > > Edit: However, i added a catch ex as exception handler and received
> > > the exception as "the file is being used by another process" although
> > > nothing is open except my program.
>
> > > Is it a streamwriter bug? Because nothing is using a text file while
> > > i'm trying to save through my project.
>
> > no, it's not a bug in the streamwriter - it's a bug in your code. and
> > if your code for loading the file is similar to the saving code, then
> > i can see why. you are never closing the resource. you need to call
> > close on the streamwriter (and streamreader) when you are done with
> > them....
>
> > using sr as new streamreader(myfile)
> > ' do stuff
> > end using
>
> > using the using block will ensure that the streamreader is properly
> > cleand up when the block ends. Basically, it will compile like you
> > had done something like:
>
> > dim sr as streamreader = nothing
> > try
> > sr = new streamreader(myfile)
> > ' do stuff
> > finally
> > if not isnothing(sr) then
> > sr.dispose()
> > end finally
>
> > you need to do the same with your streamreader.
>
> > --
> > Tom Shelton
>
> I was using this for streamwriter also of streamreader before i posted
> with no help:
> Try
> .....
> Catch
>
> Finally
> If Not myStreamWriter Is Nothing Then
> myStreamWriter.Close()
> End If- Hide quoted text -
>
> - Show quoted text -

There are only two possibilties here... 1) You aren't closing one of
your streams properly - that's why I suggest using a using block,
since it will guarentee they are closed. 2) The file really is locked
by another process.

I would suggest for one, that you make sure you aren't "swallowing"
exceptions. Exceptions that are causing you to bypass your close.
The close in every case should be in a finally block, or you should
use the stream in a using block.

This is not a bug in the stream classes - there is a bug in your code
somewhere, or we do not have sufficient information to give you a
proper answer.

--
Tom Shelton