File splitting

[Jon]

I am not too familiar with working with files, so I'd like some advice. I
need to write a function for my program that take large text files (> 150
MB) and splits them into several text files of 1000 lines each. What is the
most efficient method of doing this with the framework?

Thanks

--

*************** ******
Jon

[Cor]

Hi Jon,

A text file you can only read from the start till the end, so first a
question, what is the structure of that textfile (organised lines), plain
text, even a word document some call a text file etc.

With some more information I think some of us can help you maybe?

Now it can not be more than read it and make a new file after 100 lines.

Cor

[Jon]

It is an ASCII text file with thousands of individual lines (about 50
characters per line). The only way I could think to do it was what you
mentioned, open the file, read in 1000 lines, write those to a file. Read
in another 1000 lines, write to a file, etc...but, that seems terribly
inefficient.

Thanks!

Jon
"Cor" <no*@non.com> wrote in message
news:Oz******** ******@TK2MSFTN GP10.phx.gbl...

Hi Jon,

A text file you can only read from the start till the end, so first a
question, what is the structure of that textfile (organised lines), plain
text, even a word document some call a text file etc.

With some more information I think some of us can help you maybe?

Now it can not be more than read it and make a new file after 100 lines.

Cor

[Cor]

Hi Jon,

I think that will be the most efficient way to do it if that fits your
problem.

That gives the fewest IO and memory usage.

All other methods will cost you more.

Cor

[Jon]

"Cor" <no*@non.com> wrote in message
news:e%******** ********@TK2MSF TNGP11.phx.gbl. ..

Hi Jon,

I think that will be the most efficient way to do it if that fits your
problem.

That gives the fewest IO and memory usage.

All other methods will cost you more.

Cor

Thanks

[Herfried K. Wagner [MVP]]

* "Jon" <ru*******@hotm ail.com> scripsit:

I am not too familiar with working with files, so I'd like some advice. I
need to write a function for my program that take large text files (> 150
MB) and splits them into several text files of 1000 lines each. What is the
most efficient method of doing this with the framework?

Have a look at the 'StreamReader' and 'StreamWriter' classes.

Basic code for reading the lines of a file:

\\\
Imports System.IO
..
..
..
Dim sr As New StreamReader("C :\WINDOWS\WIN.I NI")
Dim strLine As String
strLine = sr.ReadLine()
Do Until strLine Is Nothing
MsgBox(strLine)
strLine = sr.ReadLine()
Loop
sr.Close()
///

You can add a line number counter to detect when a new file should be
started. Writing a file can be done with the 'StreamWriter' class
(method 'WriteLine').

--
Herfried K. Wagner
MVP · VB Classic, VB.NET
<http://www.mvps.org/dotnet>

<http://www.plig.net/nnq/nquote.html>