how can I lock a file?

[MrPolite]

umm I don't want the user to be able to move/delete a certain file when my app is running. Is there a way to "lock" a certain file without having it opened?

[Edneeis]

I don't think so not without having it opened.

[briancps]

in VB6 you could open it as a random file, record length 1 character and LOCK #fn,1. Anyone who tries to access the file gets an error. CAN you do something similar in VB.NET ??

[nemaroller]

Well, thats the same solution you would use in Vb.Net

http://www.vbwm.com/articles/builder...p?ArticleID=15

' attempts to open a file C:\TEST.TXT for read and write' access, and locks the file from other processes.
Dim filename As String = "C:\TEST.TXT"
Dim myFileStream As System.IO.FileStream
Try   ' attempt to open the file  myFileStream = New   System.IO.FileStream(filename, _                       System.IO.FileMode.Open, _                       System.IO.FileAccess.ReadWrite, _                       System.IO.FileShare.None)
 
Catch   ' display an error to the user 
MessageBox.Show("Could not open file. Make sure " &              filename & "exists.") 
Finally 
If myFileStream.CanRead Then  
  ' read from the file here
 
  ' close the file when you are done
    myFileStream.Close()
End If
 
End Try

[MrPolite]

well yeah I can open the file... I just didnt know if I should leave the file open or not. Sounds like I have to leave it open in order to lock the file....
btw you used FileStream in your code and I always use StreamReader and StreamWriter. What's the big difference?

[Pirate]

Originally posted by MrPolite
well yeah I can open the file... I just didnt know if I should leave the file open or not. Sounds like I have to leave it open in order to lock the file....
btw you used FileStream in your code and I always use StreamReader and StreamWriter. What's the big difference?

from Microsoft Documentation..

StreamReader
Implements a TextReader that reads characters from a byte stream in a particular encoding

StreamWriter
Implements a TextWriter for writing characters to a stream in a particular encoding.

[MrPolite]

Originally posted by pirate
from Microsoft Documentation..

hmm so it sounds like that they are for text files