I have this script saved in "test.vbs":
Set FSO = CreateObject("Scripting.FileSystemObject")
Set File = FSO.OpenTextFile(workFolder &"\test.txt", 2, True)
File.Write "testing"
File.Close
Set File = Nothing
Set FSO = Nothing
Set workFolder = Nothing
When I run the script I want to pass the value of the "workFolder" variable.
How can I do this? Can I do it? Something like "cscript test.vbs workFolder:'C:\temp\'" perhaps?
Bonus question: Is it neccessary to clean up the passed variable with "Set workFolder = Nothing" or does VBSCript do that automatically when it terminates? Maybe "Set File = Nothing" and "Set FSO = Nothing" is unneccessary also? Please let me know if you know the answer to both these questions.
You can use WScript.Arguments
to access the arguments passed to your script.
Calling the script:
cscript.exe test.vbs "C:\temp\"
Inside your script:
Set File = FSO.OpenTextFile(WScript.Arguments(0) &"\test.txt", 2, True)
Don't forget to check if there actually has been an argument passed to your script. You can do so by checking the Count
property:
if WScript.Arguments.Count = 0 then
WScript.Echo "Missing parameters"
end if
If your script is over after you close the file then there is no need to set the variables to Nothing
. The resources will be cleaned up automatically when the cscript.exe process terminates. Setting a variable to Nothing
usually is only necessary if you explicitly want to free resources during the execution of your script. In that case, you would set variables which contain a reference to a COM object to Nothing
, which would release the COM object before your script terminates. This is just a short answer to your bonus question, you will find more information in these related questions:
Is there a need to set Objects to Nothing inside VBA Functions
When must I set a variable to “Nothing” in VB6?
Inside of VBS you can access parameters with
Wscript.Arguments(0)
Wscript.Arguments(1)
and so on. The number of parameter:
Wscript.Arguments.Count
Each argument passed via command line can be accessed with: Wscript.Arguments.Item(0) Where the zero is the argument number: ie, 0, 1, 2, 3 etc.
So in your code you could have:
strFolder = Wscript.Arguments.Item(0)
Set FSO = CreateObject("Scripting.FileSystemObject")
Set File = FSO.OpenTextFile(strFolder, 2, True)
File.Write "testing"
File.Close
Set File = Nothing
Set FSO = Nothing
Set workFolder = Nothing
Using wscript.arguments.count, you can error trap in case someone doesn't enter the proper value, etc.
MS Technet examples
Try This To Get All Args :
Set Args=WSH.Arguments
For x=0 To Args.Count-1
WSH.Echo "Arg_"&x+1&" = "&Args(x)
Next
To answer your bonus question, the general answer is no, you don't need to set variables to "Nothing" in short .VBS scripts like yours, that get called by Wscript or Cscript.
The reason you might do this in the middle of a longer script is to release memory back to the operating system that VB would otherwise have been holding. These days when 8GB of RAM is typical and 16GB+ relatively common, this is unlikely to produce any measurable impact, even on a huge script that has several megabytes in a single variable. At this point it's kind of a hold-over from the days where you might have been working in 1MB or 2MB of RAM.
You're correct, the moment your .VBS script completes, all of your variables get destroyed and the memory is reclaimed anyway. Setting variables to "Nothing" simply speeds up that process, and allows you to do it in the middle of a script.