CreateDifferencingVirtualHardDisk method of the Msvm_ImageManagementService class

uint32 CreateDifferencingVirtualHardDisk(
  [in]   string Path,
  [in]   string ParentPath,
  [out]  CIM_ConcreteJob REF Job
);

using System;
using System.Management;

namespace HyperVSamples
{
    class CreateDiffVHD
    {
        static void CreateDifferencingVirtualHardDisk(string path, string parentPath)
        {
            ManagementScope scope = new ManagementScope(@"root\virtualization", null);
            ManagementObject imageService = Utility.GetServiceObject(scope, "Msvm_ImageManagementService");

            ManagementBaseObject inParams = imageService.GetMethodParameters("CreateDifferencingVirtualHardDisk");
            inParams["ParentPath"] = parentPath;
            inParams["Path"] = path;
            ManagementBaseObject outParams = imageService.InvokeMethod("CreateDifferencingVirtualHardDisk", inParams, null);
            if ((UInt32)outParams["ReturnValue"] == ReturnCode.Started)
            {
                if (Utility.JobCompleted(outParams, scope))
                {
                    Console.WriteLine("{0} was created successfully.", inParams["Path"]);
                }
                else
                {
                    Console.WriteLine("Unable to create {0}", inParams["Path"]);
                }
            }

            inParams.Dispose();
            outParams.Dispose();
            imageService.Dispose();
        }

        static void Main(string[] args)
        {
            if (args != null && args.Length != 2)
            {
                Console.WriteLine("Usage: CreateDiffVHD path, parentPath");
                return;
            }
            CreateDifferencingVirtualHardDisk(args[0], args[1]);
        }
    }
}

option explicit 

dim objWMIService
dim computerName
dim managementService
dim fileSystem

const JobStarting = 3
const JobRunning = 4
const JobCompleted = 7
const wmiStarted = 4096



const method = "CreateDifferencingVirtualHardDisk"

Main()

'-----------------------------------------------------------------
' Main routine
'-----------------------------------------------------------------
Sub Main()

    dim path, parentPath, computer, objArgs
    
    set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")

    computer = "."
    set objWMIService = GetObject("winmgmts:\\" & computer & "\root\virtualization")
    set managementService = objWMIService.ExecQuery("Select * from Msvm_ImageManagementService").ItemIndex(0)

    set objArgs = WScript.Arguments
    if WScript.Arguments.Count = 2 then
       path = objArgs.Unnamed.Item(0)
       parentPath = objArgs.Unnamed.Item(1)
    else
       WScript.Echo "usage: cscript CreateDiffVHD.vbs path ParentPath"
       WScript.Quit(1)
    end if

    if ExecuteCreateDiffVHD(path, parentPath) then
       WriteLog "Done"
       WScript.Quit(0)
    else
        WriteLog "CreateDiffVHD failed"
        WScript.Quit(1)
    end if
End Sub


'-----------------------------------------------------------------
' Execute CreateDifferencingVirtualHardDisk
'-----------------------------------------------------------------
Function ExecuteCreateDiffVHD(path, parentPath)
    WriteLog Format2("Sub ExecuteCreateDiffVHD({0}, {1})",  Path, ParentPath)
    
    dim objInParam, objOutParams
    
    ExecuteCreateDiffVHD = false

    set objInParam = managementService.Methods_("CreateDifferencingVirtualHardDisk").InParameters.SpawnInstance_()
    objInParam.Path = path
    objInParam.ParentPath = parentPath

    set objOutParams = managementService.ExecMethod_("CreateDifferencingVirtualHardDisk", objInParam)

    if (WMIMethodStarted(objOutParams)) then
        if (WMIJobCompleted(objOutParams)) then
            WriteLog Format2("'{0}' was created as a differencing disk of '{1}' .", Path, ParentPath)
            ExecuteCreateDiffVHD = true
        end if
    end if

End Function


'-----------------------------------------------------------------
' Handle wmi return values
'-----------------------------------------------------------------
Function WMIMethodStarted(outParam)
    WriteLog "Function WMIMethodStarted"
    
    dim wmiStatus
    
    WMIMethodStarted = false

    if Not IsNull(outParam) then
        wmiStatus = outParam.ReturnValue

        if  wmiStatus = wmiStarted then
            WMIMethodStarted = true
        else
            WriteLog Format3("Failed to create differencing disk {0} for {1} with error {2}", Path, ParentPath, wmiStatus)
        end if
   end if

End Function



'-----------------------------------------------------------------
' Handle wmi Job object
'-----------------------------------------------------------------
Function WMIJobCompleted(outParam)
    WriteLog "Function WMIJobCompleted"
    
    dim WMIJob, jobState

    set WMIJob = objWMIService.Get(outParam.Job)

    WMIJobCompleted = true

    jobState = WMIJob.JobState

    while jobState= JobRunning or jobState = JobStarting
        WriteLog Format1("In progress... {0}% completed.",WMIJob.PercentComplete)
        WScript.Sleep(1000)
        set WMIJob = objWMIService.Get(outParam.Job)
        jobState = WMIJob.JobState
    wend

    if (jobState <> JobCompleted) then
        WriteLog Format1("ErrorCode:{0}", WMIJob.ErrorCode)
        WriteLog Format1("ErrorDescription:{0}", WMIJob.ErrorDescription)
        WMIJobCompleted = false
    end if

End Function

'-----------------------------------------------------------------
' Create the console log files.
'-----------------------------------------------------------------
Sub WriteLog(line)
    dim fileStream
    set fileStream = fileSystem.OpenTextFile(".\CreateDiffVHD.log", 8, true)
    WScript.Echo line
    fileStream.WriteLine line
    fileStream.Close

End Sub

'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format3(myString, arg0, arg1, arg2)

    Format3 = Format2(myString, arg0, arg1)
    Format3 = Replace(Format3, "{2}", arg2)

End Function

'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format2(myString, arg0, arg1)
    Format2 = Format1(myString, arg0)
    Format2 = Replace(Format2, "{1}", arg1)
End Function

'------------------------------------------------------------------------------
' The string formatting functions to avoid string concatenation.
'------------------------------------------------------------------------------
Function Format1(myString, arg0)
    Format1 = Replace(myString, "{0}", arg0)
End Function