Fiddling around with it, it seems that StreamReader loads the whole file into
memory on the first read. That's an ... interesting ... design.

Dim strOutput As String = ""
Dim strFilename As String =
My.Computer.FileSystem.SpecialDirectories.MyDocuments & "\FileIODemo.txt"
Using fs As New FileStream(strFilename, FileMode.Create,
FileAccess.Write, FileShare.None)
Using sw As New StreamWriter(fs, System.Text.Encoding.Unicode)
sw.WriteLine("abc")
sw.WriteLine("def")
sw.WriteLine("ghijkl")
sw.WriteLine("mno")
sw.WriteLine("pqrs")
sw.WriteLine("tuvwxyz")
End Using
End Using

Using fs As New FileStream(strFilename, FileMode.Open,
FileAccess.Read, FileShare.None)
Using sr As New StreamReader(fs, System.Text.Encoding.Unicode)
MsgBox("Stream position before first read: " & fs.Position)
strOutput &= sr.ReadLine & vbCrLf
MsgBox("Stream position after first read: " & fs.Position)
strOutput &= sr.ReadLine & vbCrLf
strOutput &= sr.ReadLine & vbCrLf
fs.Seek(0, SeekOrigin.Begin) 'does nothing!!
strOutput &= sr.ReadLine & vbCrLf
strOutput &= sr.ReadLine & vbCrLf
strOutput &= sr.ReadLine & vbCrLf
End Using
End Using
MsgBox(strOutput)

The position after the first read is byte 78 - which is the end of the file.

26 characters = 52 bytes
BOM = 2 bytes
6 CRLFs = 24 bytes
---------------------
TOTAL = 78 bytes

The OP will need to create a new StreamReader, or use a BinaryReader instead.


--
David Streeter
Synchrotech Software
Sydney Australia


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