PressKey method of the Msvm_Keyboard class
Simulates a key press. When successful the key will be in the down state.
Syntax
uint32 PressKey(
[in] uint32 keyCode
);
Parameters
-
keyCode [in]
-
Type: uint32
The virtual-key code of the key to press. For the list for virtual-key codes, see Virtual-Key Codes.
Return value
Type: uint32
A return value of zero indicates success. A nonzero value indicates a failure to modify the key state.
-
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 used (32774)
-
Invalid state for this operation (32775)
-
Incorrect data type (32776)
-
System is not available (32777)
-
Out of memory (32778)
Remarks
The PressKey method maps references to the VK_MENU (18), VK_CONTROL (17), and VK_SHIFT (16) to VK_LMENU (164), VK_LCONTROL (162), and VK_LSHIFT (160), respectively, because the VK_MENU, VK_CONTROL, and VK_SHIFT virtual key codes do not represent real keys on a keyboard.
Access to the Msvm_Keyboard class might be restricted by UAC Filtering. For more information, see User Account Control and WMI.
Examples
The following C# sample simulates a key press. The referenced utilities can be found in Common utilities for the virtualization samples (V2).
using System;
using System.Management;
namespace HyperVSamples
{
class PressKeyClass
{
static ManagementObject GetComputerKeyboard(ManagementObject vm)
{
ManagementObjectCollection keyboardCollection = vm.GetRelated
(
"Msvm_Keyboard",
"Msvm_SystemDevice",
null,
null,
"PartComponent",
"GroupComponent",
false,
null
);
ManagementObject keyboard = null;
foreach (ManagementObject instance in keyboardCollection)
{
keyboard = instance;
break;
}
return keyboard;
}
static void PressKey(string vmName, int keyCode)
{
ManagementScope scope = new ManagementScope(@"root\virtualization\v2", null);
ManagementObject vm = Utility.GetTargetComputer(vmName, scope);
ManagementObject keyboard = GetComputerKeyboard(vm);
ManagementBaseObject inParams = keyboard.GetMethodParameters("PressKey");
inParams["keyCode"] = keyCode;
ManagementBaseObject outParams = keyboard.InvokeMethod("PressKey", inParams, null);
if ((UInt16)outParams["ReturnValue"] == ReturnCode.Completed)
{
string.Format("Key {0} was pressed on {1}", keyCode, vm["ElementName"]);
}
else
{
string.Format("Unable to press key {0}' on {1}", keyCode, vm["ElementName"]);
}
inParams.Dispose();
outParams.Dispose();
keyboard.Dispose();
vm.Dispose();
}
static void Main(string[] args)
{
if (args != null && args.Length != 2)
{
Console.WriteLine("Usage: PressKey vmName keyCode");
return;
}
string vmName = args[0];
int keyCode = int.Parse(args[1]);
PressKey(args[0], keyCode);
}
}
}
The following Visual Basic Scripting Edition (VBScript) sample simulates a key press.
option explicit
dim objWMIService
dim fileSystem
const wmiSuccessful = 0
Main()
'-----------------------------------------------------------------
' Main routine
'-----------------------------------------------------------------
Sub Main()
dim computer, objArgs, vmName, computerSystem, keycode, keyboard
set fileSystem = Wscript.CreateObject("Scripting.FileSystemObject")
computer = "."
set objWMIService = GetObject("winmgmts:\\" & computer & "\root\virtualization\v2")
set objArgs = WScript.Arguments
if WScript.Arguments.Count = 2 then
vmName= objArgs.Unnamed.Item(0)
keycode = objArgs.Unnamed.Item(1)
else
WScript.Echo "usage: cscript PressKey.vbs vmName keycode"
WScript.Quit
end if
set computerSystem = GetComputerSystem(vmName)
set keyboard = GetComputerKeyboard(computerSystem)
if PressKey(keyboard, keycode) then
WriteLog "Done"
WScript.Quit(0)
else
WriteLog "PressKey failed"
WScript.Quit(1)
end if
End Sub
'-----------------------------------------------------------------
' Retrieve Msvm_VirtualComputerSystem from base on its ElementName
'
'-----------------------------------------------------------------
Function GetComputerSystem(vmElementName)
dim query
On Error Resume Next
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
'-----------------------------------------------------------------
' Retrieve Msvm_Keyboard from given computer system
'
'-----------------------------------------------------------------
Function GetComputerKeyboard(computerSystem)
dim query
On Error Resume Next
query = Format1("ASSOCIATORS OF {{0}} WHERE resultClass = Msvm_Keyboard", computerSystem.Path_.Path)
set GetComputerKeyboard = 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
'-----------------------------------------------------------------
' Press the key with the given key code on the given keyboard
'-----------------------------------------------------------------
Function PressKey(keyboard, keyCode)
WriteLog Format2("PressKey({0}, {1})", keyboard.ElementName, keyCode)
dim objInParam, objOutParams
PressKey = false
set objInParam = keyboard.Methods_("PressKey").InParameters.SpawnInstance_()
objInParam.keyCode = keyCode
set objOutParams = keyboard.ExecMethod_("PressKey", objInParam)
if objOutParams.ReturnValue = wmiSuccessful then
WriteLog Format2("The key with code '{0}' is typed on {1}.", keyCode, keyboard.ElementName)
PressKey = true
end if
End Function
'-----------------------------------------------------------------
' Create the console log files.
'-----------------------------------------------------------------
Sub WriteLog(line)
dim fileStream
set fileStream = fileSystem.OpenTextFile(".\PressKey.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
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows 8 [desktop apps only] |
| Minimum supported server |
Windows Server 2012 [desktop apps only] |
| Namespace |
Root\Virtualization\V2 |
| MOF |
|
| DLL |
|
See also
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