VBS Run cmd.exe output to a variable; not text file - vbscript

Question

This is what I have so far. It works; outputing the folder path to temp to a text file.
What I really want, is to output the data to a variable. Every example I see online, show how to do this using something like:
set objScriptExec = wshShell.Exec (strCommand)
followed by
strresult = LCase(objScriptExec.StdOut.ReadAll. // code
I want this to run with Run, not Exec, because I want the command prompt windows to be hidden as I will performing many commands with the code below. How can I capture that output to a variable?
Set wsShell = CreateObject("WScript.Shell")
strCommand = "cmd /c echo %temp% > %temp%\test.txt"
wsShell.Run strcommand,0,True

Answer 1

This may be done with the Windows Script Host Exec command. StdOut, StdIn, and StdErr may all be accessed, and ERRORLEVEL is available when the command completes.
Dim strMessage, strScript, strStdErr, strStdOut
Dim oExec, oWshShell, intErrorLevel
Dim ComSpec
Set oWshShell = CreateObject("WScript.Shell")
ComSpec = oWshShell.ExpandEnvironmentStrings("%comspec%")
intErrorLevel = 0
strScript = ComSpec & " /C echo %temp%"
On Error Resume Next
Set oExec = oWshShell.Exec (strScript)
If (Err.Number <> 0) Then
strMessage = "Error: " & Err.Message
intErrorLevel = 1
Else
Do While oExec.Status = 0
Do While Not oExec.StdOut.AtEndOfStream
strStdOut = strStdOut & oExec.StdOut.ReadLine & vbCrLf
Loop
Do While Not oExec.StdErr.AtEndOfStream
strStdErr = strStdErr & oExec.StdErr.ReadLine & vbCrLf
Loop
WScript.Sleep 0
Loop
intErrorLevel = oExec.ExitCode
strMessage = strStdOut & strStdErr & CStr(intErrorLevel)
End If
WScript.Echo (strMessage)
NOTE: Replacing "ReadLine" above with "Read(1)" accomplishes the same thing, but adds an ability to process characters rather than whole lines.

Answer 2

Of course Wscript.Shell would be a lot easier, but, since you want more fine grain control of your session, consider using Win32_Process. Usually, one uses this to control the placement of a new window, but, in your case, you want it hidden, so I set startupInfo.ShowWindow = 0 which means SW_HIDE. The following declares a VBScript function called RunCmd and which will run a command in an invisible window saving the output to a text file and then return the contents of the text file to the caller. As an example, I invoke RunCmd with the HOSTNAME command:
Function RunCmd(strCmd)
Dim wmiService
Set wmiService = GetObject("winmgmts:\\.\root\cimv2")
Dim startupInfo
Set startupInfo = wmiService.Get("Win32_ProcessStartup")
Dim fso
Set fso = CreateObject("Scripting.FileSystemObject")
Dim cwd
cwd = fso.GetAbsolutePathname(".")
startupInfo.SpawnInstance_
startupInfo.ShowWindow = 0
' startupInfo.X = 50
' startupInfo.y = 50
' startupInfo.XSize = 150
' startupInfo.YSize = 50
' startupInfo.Title = "Hello"
' startupInfo.XCountChars = 36
' startupInfo.YCountChars = 1
Dim objNewProcess
Set objNewProcess = wmiService.Get("Win32_Process")
Dim intPID
Dim errRtn
errRtn = objNewProcess.Create("cmd.exe /c """ & strCmd & """ > out.txt", cwd, startupInfo, intPID)
Dim f
Set f = fso.OpenTextFile("out.txt", 1)
RunCmd = f.ReadAll
f.Close
End Function
MsgBox RunCmd("HOSTNAME")
References:
Create method of the Win32_Process class
Win32_ProcessStartup class