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How to pass parameters from batch file to vb.net program?

sasllc asked
Last Modified: 2012-06-27
The program is vb.net 2005, and I run it from a dos batch file.  Now I need to optionally send a parameter that the vb program can recognize and work with.  For example, in my batch file I might call the program with a parameter like this:

call ecotpc.exe ABC

And, in my ecotpc vb program, I'd like to be able to handle the optional parameter something like this:

If %1 = "" then null routine...
psWork1 = %1

The problem is that I don't know the syntax to "capture" that variable, and I don't know what extra code I might need to add to the top section of my code (such as "imports", etc.)

Any clear, detailed example would be greatly appreciated!  TIA
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Ahhh, it's been ages since I tried something like this. VB6 was something like Command$, in .Net look at the values contained in Environment.GetCommandLineArgs()...

looking, here is a link to two methods of achieving what you are after. I believe the second way is easiest, but overriding main is just as good. If you are using a form, you will have to rely on method 2


'Method 1 - override Main'
Shared Sub Main(ByVal args As String())
    For Each arg As String In args
    Next arg 
End Sub
'Method 2'
For Each arg As String In Environment.GetCommandLineArgs()
Next arg

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OK, I almost have it working, but I need additional specifics.  Using method 2 above, I changed the "console.writeline" to messagebox.show(arg).  And then, if the batch file command line says "call ecotpc.exe ABC", I get two message boxes...the first one says "ecotpc" (the program name), and the second one says "ABC" (the parameter I keyed in)--and the "ABC" is the parameter I'm interested in.  

So how can I specifically access only the "ABC" in this case and place it in a variable such as psWork1?  I tried "psWork1 = arg(2)" (hoping I would get the 2nd string), which does not work, but I don't know what else to try.

I'm trying to get to something simple like this concept:

If arg = "" then null routine...
psWork1 = arg

I know I will only have one parameter, at most, and I need to know how to "get to" that one parameter--such as "ABC" in this test I ran.

in which case arg(0) is the command line itself (minus arguments), arg(1) is the 1st argument, arg(2) is the 2nd and so on...

' for example '
' will always be 1 more than the number of parameters - in your case, it will be 2 '
' Option 1 - will always return the last paramater '
MsgBox(Environment.GetCommandLineArgs(Environment.GetCommandLineArgs.Count - 1))
' Option 2 - will always return the 1st parameter '
' since you only have 1 parameter, they will return the same value '

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If Environment.GetCommandLineArgs.Count = 1 then 
 ' null routine... 1 = command line only, 2 means we have parameter '
 psWork1 = Environment.GetCommandLineArgs(1)
end if

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When I try to use this syntax:

If Environment.GetCommandLineArgs.count = 1 Then

I get this error: 'count' is not a member of 'System.Array'.  It gives me a long list of other options after the '.' -- which I don't know how to use -- but 'count' is not one of them.  Any ideas?

And if not, I have been able to do a workaround based on your information.  But it would be nice to able to use "clean code" like you've shown instead--if I could get .count to work.
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I have verified the above works, and it seems that 2008 (for some reason) is more forgiving. After doing a little research I have found that Environment.GetCommandLineArgs is an Array and not a collection, hence that is why you are getting the error. As a rule (as I have found out) Length is used for Arrays, and Count is used for Collections. Still not sure why it works for me though
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