.NET Framework - Template for Command-Line utility

Asked By Phil Hellmuth

29-Oct-08 01:01 PM

I'm fairly new to VS/VB.net.  I want to create a command line utility
that uses two parameters, reads a file (first parm), and writes to
another file (2nd parm).  Which VS/VB.net template should I use to get
started?  Thanks in advance.

30-Oct-08 06:45 AM

Start New Project, Choose "Console Application".

BTW, is all your intention to copy files using like
System.IO.File.Copy?

Thanks,

Onur Guzel

29-Oct-08 01:18 PM

You'll want to create a Console application.  Your main should probably
look like this:

Public Function Main (ByVal args() As String) As Integer
' args contains all the arguments passed to your application
' assuming that the arguments are correct (you'll want to put
' in validation/parsing code here...

Dim inputFile As String = args(0)
Dim outputFile As String = args(1)

' do cool stuff

' You will most likely want to return an exit code
' 0 means no error, non-zero means a problem - you might
' want to have different codes for different problems, but
' that's up to you.  You don't have to do this at all :)
' you could make Main a sub instead of a function, but
' most command line apps return an exit code to the OS -
' so it's a good idea to do the same.
Return AnExitCode
End Function

HTH

--
Tom Shelton

29-Oct-08 02:13 PM

Thanks for your response.  This really helps.  Unfortunately, I'm stuck
with what I'm trying to do next.  I want to see if the files specified
in the arguments exist, using the FileExists function.  However, I don't
know what reference to use to import System.File.IO (as I said, I'm new
to this).  Next, I want to read each byte in the input file and write it
to the output file if it's less than 128 (ascii).  Is this relatively
simple?

29-Oct-08 03:04 PM

Have you tried the Help for FileExists? Often there will be a code
snippet to show how it works. Also try googling for sample code.

--

Dennis

29-Oct-08 03:11 PM

Actually, it is :)  Here is some air-code, this untested, and is infact not
likely to work the first try...  I might have my indexing off or some minor
syntax issues, but it should be enough to get you started :)

Option Explict On
Option Strict On

Imports System
Imports System.IO

Public Function Main (ByVal args() As String) As Integer
' args contains all the arguments passed to your application
' assuming that the arguments are correct (you'll want to put
' in validation/parsing code here...

Dim inputFile As String = args(0)
Dim outputFile As String = args(1)
Dim anExiteCode As Integer = 0
Dim inBuffer() As Byte = new Byte(2048)
Dim outBuffer() As Byte = new Byte(2048)
Dim bytesRead As Integer = 0
dim bytesWritten = 0

Try
Using inFile As New FileStream(inputFile, FileMode.Open, FileAccess.Read), _
outFile As New FileStream(ouputFile, FileMode.Create, FileAccess.Write)

bytesRead = inFile.Read(inBuffer, 0, inBuffer.Length)
while bytesRead > 0
for i as integer = 0 to bytesRead - 1
if inbuffer(i) > 128 then
outBuffer(bytesWritten) = inbuffer(i)
bytesWritten += 1
end if
next i
outFile.Write(outBuffer, 0, bytesWritten)
bytesRead = inFile.Read(inBuffer, 0, inBuffer.Length)
end while
End Using
Catch ex As Exception
anExitCode = 1
End Catch

' You will most likely want to return an exit code
' 0 means no error, non-zero means a problem - you might
' want to have different codes for different problems, but
' that's up to you.  You don't have to do this at all :)
' you could make Main a sub instead of a function, but
' most command line apps return an exit code to the OS -
' so it's a good idea to do the same.
Return anExitCode
End Function

Anyway, hth

--
Tom Shelton

29-Oct-08 03:15 PM

Actually, i did not notice your question about references :)  You do not need to
add any additional references - just add the Imports System.IO.

--
Tom Shelton