Access to .txt [VB.NET]

Question

I've developed a multi-user application. One user saves a string to a text file, other users have to read this string in a background process.

My problem is: when some users open the file to read the string, another user that wants to save a new string can't write to the file. I would like to implement a system that checks if the file is opened or not, and in case it is, waits a few seconds and retries.

What is the function or command to look if the file is already opened?

Don't open file as exclusive. Open it as shared. So it would be possible for file to be opened by multiple instances at the same time. — Pradeep Kumar, Sep 21 '15 at 06:41

Pietro Z. · Answer 1 · 2015-09-21T08:45:13.843

I solved my problem using tips:

i've replaced this code:

         ip_acquisito = My.Computer.FileSystem.ReadAllText(path_elenco & "\ip.txt")

with this code:

     Using fs As FileStream = File.Open(path_elenco & "\ip.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite)
             Dim b(1024) As Byte
             Dim temp As UTF8Encoding = New UTF8Encoding(True)

             Do While fs.Read(b, 0, b.Length) > 0
                 ip_acquisito = temp.GetString(b)
             Loop
     End Using

score 0 · Accepted Answer · edited May 23 '17 at 12:23

0

There are quite a few patterns you can deal with. Two I'd recommend would be:

edited May 23 '17 at 12:23

Community

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answered Sep 21 '15 at 08:39

Waescher

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Access to .txt [VB.NET]

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