SWbemNamedValueSet object

An SWbemNamedValueSet object is a collection of SWbemNamedValue objects. The methods and properties of SWbemNamedValueSet are used principally to send more information to providers when submitting certain calls to WMI. All calls in SWbemServices, and some calls in SWbemObject, take an optional parameter that is an object of this type. A client can add information to an SWbemNamedValueSet object, and send the SWbemNamedValueSet object with the call as one of the parameters. This object can be created by the VBScript CreateObject call.

For more information, see Accessing a Collection.

Note

Important - If possible, do not use this mechanism because it can break the uniform access model that is the basis of WMI. If a provider does use this mechanism, it is important that this mechanism is used as sparingly as possible. If a provider requires a large amount of highly specific context information to respond to a request, all clients must be coded to provide this information. This mechanism allows you to access such providers, if necessary.

An SWbemNamedValueSet object is a collection of SWbemNamedValue elements. These items are added to the collection using the SWbemNamedValueSet.Add method. They are removed using the SWbemNamedValueSet.Remove method and retrieved using the SWbemNamedValueSet.Item method. You can access the methods to fill in any context information that is required by a dynamic provider. After you call one of the SWbemServices methods, you can reuse the SWbemNamedValueSet object for another call.

The underlying provider determines the information that is contained in an SWbemNamedValueSet object. WMI makes no use of the information, but simply forwards it to the provider. Providers must publish the context information they require to service requests.

Members

The SWbemNamedValueSet object has these types of members:

• Methods
• Properties

Methods

The SWbemNamedValueSet object has these methods.

Method	Description
Add	Adds an SWbemNamedValue object to the collection.
Clone	Makes a copy of this SWbemNamedValueSet collection.
DeleteAll	Removes all items from the collection, making the SWbemNamedValueSet object empty.
Item	Retrieves an SWbemNamedValue object from the collection. This is the default method of the object.
Remove	Removes an SWbemNamedValue object from the collection.

Properties

The SWbemNamedValueSet object has these properties.

Property	Access type	Description
Count	Read-only	The number of items in the collection.

Examples

The following VBScript sample demonstrates the manipulation of named value sets, in the case that the named value is an array type.

Set Context = CreateObject("WbemScripting.SWbemNamedValueSet")

On Error Resume Next

Context.Add "n1", Array (1, 2, 3)
str = "The initial value of n1 is {"
for x=LBound(Context("n1")) to UBound(Context("n1"))
 str = str & Context("n1")(x)
 if x <> UBound(Context("n1")) Then
  str = str & ", "
 End if
next
str = str & "}"
WScript.Echo str

WScript.Echo ""

' report the value of an element of the context value
v = Context("n1")
WScript.Echo "By indirection the first element of n1 has value:",v(0)

' report the value directly
WScript.Echo "By direct access the first element of n1 has value:", Context("n1")(0)

' set the value of a single named value element
Context("n1")(1) = 11 
WScript.Echo "After direct assignment the first element of n1 has value:", Context("n1")(1)

' set the value of a single named value element
Set v = Context("n1")
v(1) = 345
WScript.Echo "After indirect assignment the first element of n1 has value:", Context("n1")(1)

' set the value of an entire context value
Context("n1") = Array (5, 34, 178871)
WScript.Echo "After direct array assignment the first element of n1 has value:", Context("n1")(1)

str = "After direct assignment the entire value of n1 is {"
for x=LBound(Context("n1")) to UBound(Context("n1"))
 str = str & Context("n1")(x)
 if x <> UBound(Context("n1")) Then
  str = str & ", "
 End if
next
str = str & "}"
WScript.Echo str

if Err <> 0 Then
 WScript.Echo Err.Description
 Err.Clear
End if

The following Perl sample demonstrates the manipulation of named value sets, in the case that the named value is an array type.

use strict;
use Win32::OLE;

my ( $Context, $str, $x, @v);

eval {$Context = new Win32::OLE 'WbemScripting.SWbemNamedValueSet'; };
unless($@)
{
 $Context->Add("n1", [1, 2, 3]);
 $str = "The initial value of n1 is {";
 for ($x = 0; $x < @{$Context->Item("n1")->{Value}}; $x++)
 {
  $str = $str.@{$Context->Item("n1")->{Value}}[$x];
  if ($x != (@{$Context->Item("n1")->{Value}}) - 1 )
  {
   $str = $str.", ";
  }
 }
 $str = $str."}";
 print $str,"\n\n";

 # report the value of an element of the context value
 @v = @{$Context->Item("n1")->{Value}};
 print "By indirection the first element of n1 has value:", $v[0], "\n";

 # report the value directly
 print "By direct access the first element of n1 has value:", @{$Context->Item("n1")->{Value}}[0], "\n";

 # set the value of a single named value element
 @{$Context->Item("n1")->{Value}}[1] = 11;
 print "After direct assignment the first element of n1 has value:", 
       @{$Context->Item("n1")->{Value}}[1], "\n";

 # set the value of a single named value element
 @v = @{$Context->Item("n1")->{Value}};
 $v[1] = 345;
 print "After indirect assignment the first element of n1 has value:", 
    @{$Context->Item("n1")->{Value}}[1], "\n";

 # set the value of an entire context value
 $Context->Item("n1")->{Value} = [5, 34, 178871];
 print "After direct array assignment the first element of n1 has value:", 
   @{$Context->Item("n1")->{Value}}[1], "\n";

 $str = "After direct assignment the entire value of n1 is {";
 for ($x = 0; $x < @{$Context->Item("n1")->{Value}}; $x++)
 {
  $str = $str.@{$Context->Item("n1")->{Value}}[$x];
  if ($x != (@{$Context->Item("n1")->{Value}}) - 1 )
  {
   $str = $str.", ";
  }
 }
 $str = $str."}";
 print $str,"\n";
}
else
{
 print STDERR Win32::OLE->LastError, "\n";
}

Requirements

Requirement	Value
Minimum supported client	Windows Vista
Minimum supported server	Windows Server 2008
Header	Wbemdisp.h
Type library	Wbemdisp.tlb
DLL	Wbemdisp.dll
CLSID	CLSID_SWbemNamedValueSet
IID	IID_ISWbemNamedValueSet

See also

Scripting API Objects