I'm trying to create a text file, write to it, close it, then reopen the
same file for reading (line by line). I've so far been able to successfully
open the file, write to it, then close it. I let the user decide which file
to write to, using the following code:
' File writing/reading variables
Dim SaveFileResult As SaveFileDialog
Dim TextFileStream As FileStream
Dim TextStreamWrite r As StreamWriter
Dim TextStreamReade r As StreamReader
SaveFileResult = New SaveFileDialog
SaveFileResult. Filter = "Text Files|*.txt|All Files|*.*"
SaveFileResult. FilterIndex = 0
Dim FileResult As DialogResult
FileResult = SaveFileResult. ShowDialog
If FileResult = DialogResult.OK Then
' Open file for writing
TextFileStream = SaveFileResult. OpenFile
TextStreamWrite r = New StreamWriter(Te xtFileStream)
Else ' Since they cancelled, exit sub
txtText.Focus()
txtText.Select( 0, txtText.Text.Le ngth)
Exit Sub
End If
End If
.... This works successfully. Is there a way I can then change it from
write-only access to read-only access, or would I need to close it first?
Also, how can I open it with the same filename? I'm really new to working
with files, so any help would be appreciated. Thank you very much! 5 1612
Eric,
The samples at MSDN about the streamwriter are in my idea a lot different
what you use, while for your question in my idea they are given. http://msdn.microsoft.com/library/de...classtopic.asp
You write about the close, however I see it nowhere in your code while it is
really two times needed.
As extra if you want a quick answer, than please make the code about the
problem and not about the OpenFileDialog and the SaveFileDialog as it is
now. Try than to avoid blank lines in your messages, this you can get using
the nobebook or using this program from Armin. http://www.vb-tips.com/default.aspx?...9-0487108f3513
I hope this helps,
Cor
Hi Eric,
The way I open files using a OpenFileDialog is:
1. Store the path to the file using the FileName property of the FileDialog.
2. Use one of the overloaded constructors of the FileStream class to create
a new filestream:
Dim TextFileStream As New FileStream(strF ileName, FileMode.Open,
FileAccess.Read , FileShare.None)
The FileAccess and FileShare enumerations will help you to set Readonly
or Writeonly access.
3. Create a StreamReader or Writer which will then read or write to your
selected file.
You can open the file with the same file name since the path to the file
would be stored in your variable.
Hope that helps,
Regards,
Cerebrus.
"Eric A. Johnson" <no*****@dontlo okforme.com> wrote in message
news:HI******** **********@news svr27.news.prod igy.net... I'm trying to create a text file, write to it, close it, then reopen the same file for reading (line by line). I've so far been able to
successfully open the file, write to it, then close it. I let the user decide which
file to write to, using the following code: ' File writing/reading variables
Dim SaveFileResult As SaveFileDialog
Dim TextFileStream As FileStream
Dim TextStreamWrite r As StreamWriter
Dim TextStreamReade r As StreamReader
SaveFileResult = New SaveFileDialog
SaveFileResult. Filter = "Text Files|*.txt|All Files|*.*"
SaveFileResult. FilterIndex = 0
Dim FileResult As DialogResult
FileResult = SaveFileResult. ShowDialog
If FileResult = DialogResult.OK Then
' Open file for writing
TextFileStream = SaveFileResult. OpenFile
TextStreamWrite r = New StreamWriter(Te xtFileStream)
Else ' Since they cancelled, exit sub
txtText.Focus()
txtText.Select( 0, txtText.Text.Le ngth)
Exit Sub
End If
End If ... This works successfully. Is there a way I can then change it from write-only access to read-only access, or would I need to close it first? Also, how can I open it with the same filename? I'm really new to working with files, so any help would be appreciated. Thank you very much!
Cerebrus.
Does still not work if you don't close the file after writing before you
start to read it.
The filedialog is not the qeustion in my opinion. just a way to find the
path.
Cor
Hi Cor,
I know that, of course, but in that case I must have misunderstood Eric's
question. I assumed that the FileStream would be closed before attempting
another read/write.
The way I saw it, he was creating his FileStream using the
"TextFileSt ream = SaveFileResult. OpenFile" statement, where SaveFileResult
is the SaveFileDialog.
Using this option, one has to go with the default options and is limited in
flexibility as far as Read/Write access control is concerned.
To quote the Help :
SaveFileDialog. OpenFile Method :
------------------------------------
"For security purposes, this method creates a new file with the selected
name and opens it with read/write permissions. This can cause unintentional
loss of data if you select an existing file to save to. To save data to an
existing file while retaining existing data, use the File class to open the
file using the file name returned in the FileName property."
That was what I wanted to explain in my post.
Regards,
Cerebrus.
"Cor Ligthert [MVP]" <no************ @planet.nl> wrote in message
news:uL******** ******@TK2MSFTN GP15.phx.gbl... Cerebrus.
Does still not work if you don't close the file after writing before you start to read it.
The filedialog is not the qeustion in my opinion. just a way to find the path.
Cor
Thank you both for your replies! I truly appreciate it a lot. You've been
a terrific help to me! :)
-- Eric
"Cerebrus99 " <zo*****@sify.c om> wrote in message
news:eu******** *****@TK2MSFTNG P09.phx.gbl... Hi Cor,
I know that, of course, but in that case I must have misunderstood Eric's question. I assumed that the FileStream would be closed before attempting another read/write.
The way I saw it, he was creating his FileStream using the "TextFileSt ream = SaveFileResult. OpenFile" statement, where SaveFileResult is the SaveFileDialog.
Using this option, one has to go with the default options and is limited in flexibility as far as Read/Write access control is concerned.
To quote the Help :
SaveFileDialog. OpenFile Method : ------------------------------------ "For security purposes, this method creates a new file with the selected name and opens it with read/write permissions. This can cause unintentional loss of data if you select an existing file to save to. To save data to an existing file while retaining existing data, use the File class to open the file using the file name returned in the FileName property."
That was what I wanted to explain in my post.
Regards,
Cerebrus.
"Cor Ligthert [MVP]" <no************ @planet.nl> wrote in message news:uL******** ******@TK2MSFTN GP15.phx.gbl... Cerebrus.
Does still not work if you don't close the file after writing before you start to read it.
The filedialog is not the qeustion in my opinion. just a way to find the path.
Cor
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