VB .NET Language in a Nutshell

Name

Command Function

Class

Microsoft.VisualBasic.Interaction

Syntax

Command(  )

Return Value

A String containing the command-line arguments

Description

Returns the arguments used when launching VB or an application created with VB.

Rules at a Glance

• For applications created with VB and compiled into an EXE, Command returns a string containing everything entered after the executable filename.

• If the executable has been launched with no command-line arguments, Command returns a null string.

Example

The following example demonstrates how to parse command-line arguments to set up a series of options in your executable. This example (which is bereft of all error handling) looks for a hyphen or a forward slash in the command-line arguments and assumes that the character following it is a command-line switch. Given the command-line arguments:

-d:50 -f -g -k

the program displays the following in the Immediate window:

Got option d
Option d Parameter = 50
Got option f
Got option g
Got option k

The source code is as follows:

Private Sub ParseCommandLine( ) Dim i As Integer Dim s, sChar, sParam As String Dim sPattern As String = "[-/]" For i = 1 To Len(Command) sChar = mid(Command, i, 1) If sChar = "-" or sChar = "/" Then s = Mid(Command, i + 1, 1) Select Case s Case "d" Console.WriteLine("Got option d") sParam = Mid(Command, i + 3, 2) Console.WriteLine("Option d Parameter = " & _ sParam) Case "f" Console.WriteLine("Got option f") Case "g" Console.WriteLine("Got option g") Case "k" Console.WriteLine("Got ...