Read and Write to a file

[bortiquai]

I am trying to read text from a text file, change it and the write it back to the same file. I am using the Io.streamReader and streamWriter.

I can't seem to get it to work because when it gets to the file.writeline(myFText), i receive an IOException, The file: "....MyFIle.txt" is in use"

I have tried adding file.close and file.dispose after ever instance of it, but it does not help.

Essentially, all i really want to do is add a line of text to the beginning of the file. If there is a better way to do that, i'd appreciate any suggestions.

Thank you

 

[Paszt]

Beginning with .NET framework V2, the My namespace contains functions that ease file access:

Dim fileContents As String = String.Empty
If My.Computer.FileSystem.FileExists("C:\Test.txt") Then
    fileContents = My.Computer.FileSystem.ReadAllText("C:\Test.txt")
End If
Dim myFText As String = "some random text"
fileContents = myFText & Environment.NewLine & fileContents
My.Computer.FileSystem.WriteAllText("C:\Test.txt", fileContents, False)

I created most of this code using code snippets. Right click in the code window and select 'Insert Snippet...' to view many more code snippets.

 

[SDavied]

If you provide your code that is causing the problem, I can help. I have an idea as to what your problem is, but without your code to see exactly what is going on, I'm just guessing.

 

[prabumj]

I am trying to read text from a text file, change it and the write it back to the same file. I am using the Io.streamReader and streamWriter.

I can't seem to get it to work because when it gets to the file.writeline(myFText), i receive an IOException, The file: "....MyFIle.txt" is in use"

I have tried adding file.close and file.dispose after ever instance of it, but it does not help.

Essentially, all i really want to do is add a line of text to the beginning of the file. If there is a better way to do that, i'd appreciate any suggestions.

Thank you

hi,
You must Create a filestream instance like below
Dim fs As New FileStream("C:\Documents and Settings\me.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite)

if u use this code u will never get exception

How it Helped ! Reply.

 

[Paszt]

You must Create a filestream instance like below
Dim fs As New FileStream("C:\Documents and Settings\me.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite)

That's not exactly true. As I posted above, using the My.Computer.FileSystem.ReadAllText method doesn't require the coder to create a FileStream instance. Although a FileStream instance is created by the method itself, the coder does not have to bother with creating or disposing of the instance.