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seek to end of file, delete line

I need help with seeking to the end of a file, deleting a line and saving the file. Below is my windows text file and my code so far.

Windows Text File

102,,agent_disconnect,2007-02-27 22:54:44,0xffffffff,0xffffffff,,,,000.184.00.131,000.184.00.131,,,,,,,,,,,,
102,,agent_disconnect,2007-02-27 22:54:44,0xffffffff,0xffffffff,,,,00.109.000.010,00.109.000.010,,,,,,,,,,,,
102,,agent_discon
------------------------
Code:

//Goal: read to end of file and delete the last line, then save the file as win.txt
Dim myFile As String
myFile = "c:\logfiles\winlog.txt"

Dim fs As New FileStream("myFile", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite)
fs.Seek(0, SeekOrigin.End)
'read back and remove the last line?
'now save as new file in c:\logfiles\temp\win.txt
fs.Close()

ASKER CERTIFIED SOLUTION

tpwells

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SOLUTION

Mike Tomlinson

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SOLUTION

Fernando Soto

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Mike Tomlinson

Hey Fernando...instead of rewriting the whole file, try using SetLength() to truncate the existing stream you have:
http://msdn2.microsoft.com/en-us/library/system.io.filestream.setlength.aspx

"If the given value is less than the current length of the stream, the stream is truncated."

I haven't tied it myself...but maybe:

fs.SetLength(currentPosition)
fs.Close()

Fernando Soto

Hi Idle_Mind;

You are correct of course but in this case fwsteal wanted to save it to a different file.

You have a great day. ;=)

Fernando

Mike Tomlinson

Hehe...good point Fernando!

My short term memory even amazes me sometimes... =)