vb.net How to pass a string with spaces to the command line

Question

I am trying to call an external program using Process:

    Dim strExe As String = \"E:\\Projects\\Common Files\\mktorrent.exe\"
    Dim p As New Process
             


        

Answer 1

Windows does not provide a common way of keeping arguments with spaces as single arguments. However there are a number of relatively common standards that you've tried.

So it comes down to either determining what argument processing mktorrent.exe uses or, as you're trying to pass a filename, using "MSDOS" 8.3 format for the path which will have no spaces.

For the latter, this answer points to the Win32API GetShortPathName.

Of course, 8.3 filenames can be disabled with modern Windows (all Windows NT-based systems I believe -- not that it often is). So your only full solution is to determine what argument processing mktorrent supplies.

Since your comment suggesting the quotes are not being passed through I confirmed I see 'testing' 'testing' '1 2 3' in the MsgBox output of this vbscript:

Option Explicit

Dim arg
Dim line

For Each arg in WScript.Arguments
  line = line & " '" & arg & "'"
Next

MsgBox Trim(line)

when executed using:

Dim strExe As String = "C:\Windows\System32\wscript.exe"
Dim p As New Process
Dim pinfo As New ProcessStartInfo
pinfo.UseShellExecute = False
pinfo.RedirectStandardOutput = True
pinfo.Arguments = " G:\Utils\Arguments.vbs testing ""testing"" ""1 2 3"""
pinfo.FileName = strExe
pinfo.WorkingDirectory = "G:\Utils"
pinfo.WindowStyle = ProcessWindowStyle.Normal
pinfo.CreateNoWindow = True
p.StartInfo = pinfo
p.Start()

So wscript is seeing the quotes and is accumulating three arguments for the script.

BTW I just noticed your example attempts at getting quotes around the filename modify the fn variable. Did you cater for this with the .WorkingDirectory line, which should be using the unmodified filename?