ModifyKvpItems method of the Msvm_VirtualSystemManagementService class

Modifies existing key-value pairs on a virtual machine.

Syntax

uint32 ModifyKvpItems(
  [in]  CIM_ComputerSystem REF TargetSystem,
  [in]  string                 DataItems[],
  [out] CIM_ConcreteJob    REF Job
);

Parameters

TargetSystem [in]

Type: CIM_ComputerSystem

A reference to the virtual machine on which the key-value pairs will be modified.

DataItems [in]

Type: string[]

An array of key-value pairs to be modified. Each element of the array is an embedded instance of the Msvm_KvpExchangeDataItem class. This method fails if any of the specified key-value pairs does not exist on the target system. This array can contain at most 128 elements.

Job [out]

Type: CIM_ConcreteJob

If the operation is performed asynchronously, this method will return 4096, and this parameter will contain a reference to an object derived from CIM_ConcreteJob.

Return value

Type: uint32

This method returns one of the following values.

Completed with No Error (0)

Method Parameters Checked - Job Started (4096)

Failed (32768)

Access Denied (32769)

Not Supported (32770)

Status is unknown (32771)

Timeout (32772)

Invalid parameter (32773)

System is in use (32774)

Invalid state for this operation (32775)

Incorrect data type (32776)

System is not available (32777)

Out of memory (32778)

Remarks

Access to the Msvm_VirtualSystemManagementService class might be restricted by UAC Filtering. For more information, see User Account Control and WMI.

Examples

The following C# sample modifies key-value pairs on a virtual machine. The referenced utilities can be found in Common utilities for the virtualization samples (V2).

using System;
using System.Management;

namespace HyperVSamples
{
    class ModifyKvpItemsClass
    {
        static void ModifyKvpItems(string vmName, string itemName, string itemValue)
        {
            ManagementScope scope = new ManagementScope(@"root\virtualization\v2", null);
            ManagementObject virtualSystemService = Utility.GetServiceObject(scope, "Msvm_VirtualSystemManagementService");
            ManagementBaseObject inParams = virtualSystemService.GetMethodParameters("ModifyKvpItems");
            ManagementClass kvpExchangeDataItem = new ManagementClass(scope, new ManagementPath("Msvm_KvpExchangeDataItem"), null);

            ManagementObject dataItem = kvpExchangeDataItem.CreateInstance();
            
            dataItem["Data"] = itemValue;
            dataItem["Name"] = itemName;
            dataItem["Source"] = 0;

            string[] dataItems = new string[1];
            dataItems[0] = dataItem.GetText(TextFormat.CimDtd20);

            ManagementObject vm = Utility.GetTargetComputer(vmName, scope);
            inParams["TargetSystem"] = vm.Path.Path;
            inParams["DataItems"] = dataItems;

            ManagementBaseObject outParams = virtualSystemService.InvokeMethod("ModifyKvpItems", inParams, null);

            if ((UInt32)outParams["ReturnValue"] == ReturnCode.Started)
            {
                if (Utility.JobCompleted(outParams, scope))
                {
                    Console.WriteLine("KvpItems were modified successfully.");
                }
                else
                {
                    Console.WriteLine("Failed to modify KvpItems");
                }
            }
            else if ((UInt32)outParams["ReturnValue"] == ReturnCode.Completed)
            {
                Console.WriteLine("KvpItems were modified successfully.");
            }
            else
            {
                Console.WriteLine("Modify virtual system kvp items failed with error {0}", outParams["ReturnValue"]);
            }

            inParams.Dispose();
            outParams.Dispose();
            vm.Dispose();
            dataItem.Dispose();
            virtualSystemService.Dispose();
        }

        static void Main(string[] args)
        {
            if (args != null && args.Length != 3)
            {
                Console.WriteLine("Usage: ModifyKvpItems vmName itemName itemValue");
                return;
            }
            ModifyKvpItems(args[0], args[1], args[2]);
        }
    }
}

The following Visual Basic Scripting Edition (VBScript) sample modifies key-value pairs on a virtual machine.

option explicit 

dim objWMIService
dim managementService
dim fileSystem


const JobStarting = 3
const JobRunning = 4
const JobCompleted = 7
const wmiStarted = 4096
const wmiSuccessful = 0

Main()

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

    dim computer, vmName, itemName, itemValue, myVm, objArgs
    
    set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")

    computer = "."

    set objWMIService = GetObject("winmgmts:\\" & computer & "\root\virtualization\v2")
    set managementService = objWMIService.ExecQuery("select * from Msvm_VirtualSystemManagementService").ItemIndex(0)

    set objArgs = WScript.Arguments
    if WScript.Arguments.Count = 3 then
        vmName = objArgs.Unnamed.Item(0)
        itemName = objArgs.Unnamed.Item(1)
        itemValue = objArgs.Unnamed.Item(2)
    else
        WScript.Echo "usage: cscript AddKvpItems.vbs vmName itemName itemValue"
        WScript.Quit(1)
    end if

    set myVm = GetComputerSystem(vmName)

    if ModifyKvpItems(myVm, itemName, itemValue) then

        WriteLog "Done"
        WScript.Quit(0)

    else
        WriteLog "ModifyKvpItems failed"
        WScript.Quit(1)
    end if


End Sub

'-----------------------------------------------------------------
' Retrieve Msvm_VirtualComputerSystem from base on its ElementName
'-----------------------------------------------------------------
Function GetComputerSystem(vmElementName)
    On Error Resume Next
    dim query
    query = Format1("select * from Msvm_ComputerSystem where ElementName = '{0}'", vmElementName)
    set GetComputerSystem = objWMIService.ExecQuery(query).ItemIndex(0)
    if (Err.Number <> 0) then
        WriteLog Format1("Err.Number: {0}", Err.Number)
        WriteLog Format1("Err.Description:{0}",Err.Description)
        WScript.Quit(1)
    end if
End Function

'-----------------------------------------------------------------
' RemoveVirtualSystemResource
'-----------------------------------------------------------------
Function ModifyKvpItems(computerSystem, itemName, itemValue)

    dim dataItem, dataItems, objInParam, objOutParams
    
    ModifyKvpItems = false
    
    set dataItem = objWMIService.Get("Msvm_KvpExchangeDataItem").SpawnInstance_()
    
    dataItem.Data = itemValue
    dataItem.Name = itemName
    dataItem.Source = 0
    
    dataItems = Array(1)
    dataItems(0) = dataItem.GetText_(1)
    
    set objInParam = managementService.Methods_("ModifyKvpItems").InParameters.SpawnInstance_()
    objInParam.TargetSystem = computerSystem.Path_.Path
    objInParam.dataItems = dataItems
    
    set objOutParams = managementService.ExecMethod_("ModifyKvpItems", objInParam)

    if objOutParams.ReturnValue = wmiStarted then
        if (WMIJobCompleted(objOutParams)) then
            ModifyKvpItems = true
        end if
    elseif objOutParams.ReturnValue = wmiSuccessful then
        ModifyKvpItems = true
    else
        WriteLog Format1("ModifyKvpItems failed with {0}", objOutParams.ReturnValue)
    end if

End Function

'-----------------------------------------------------------------
' Handle wmi Job object
'-----------------------------------------------------------------
Function WMIJobCompleted(outParam)

    dim WMIJob, jobState
    WMIJobCompleted = true

    set WMIJob = objWMIService.Get(outParam.Job)
    
    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 (WMIJob.JobState <> JobCompleted) then
        WriteLog Format1("ErrorDescription:{0}", WMIJob.ErrorDescription)
        WriteLog Format1("ErrorCode:{0}", WMIJob.ErrorCode)
        WMIJobCompleted = false
    end if
    
End Function

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

End Sub


'------------------------------------------------------------------------------
' 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

Requirements

See also

ModifyKvpItems (V1)

Msvm_VirtualSystemManagementService