How to: Get and Set WMI Object Properties

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To read and write Windows Management Instrumentation (WMI) object property values, you:

• Get and set property and qualifier values.
• Load and save configurations.

Getting and Setting Properties on WMI Objects

Use properties to provide information about the characteristics of a WMI object. For more information about Speech Server WMI classes, see Speech Server WMI Classes.

To read property values

• Use code similar to the following sample.

  Note

  All Speech Server classes inherit from the SWbemObject object, which explains why the SWbemObject.Properties_ property is available in the following sample.

  Set objMSS = GetObject("winmgmts:root\MSSV2:MSS=@")
  ' Read each member of SWbemObject.Properties_
  For Each p in objMSS.Properties_
  ' Display the values of the Name and Value properties of the SWbemProperty object  
   If p.IsArray Then
        WScript.Echo p.Name, "=", Join(p.Value)
       Else
        WScript.Echo p.Name, " = ", p.Value
     End If
  Next
  

To write property values of Speech Server objects

• To write a property value, you must, at a minimum, retrieve an instance of the class containing the property, assign the property a value, and use the Put_ method to update the value in the object. The following sample gets the MSS object (using the GetObject function), sets the UpperMemoryThreshold property, and saves the change.

  Set objMSS = GetObject("winmgmts:root\MSSV2:MSS=@")
  objMSS.UpperMemoryThreshold=1800
  objMSS.Put_()
  

Reading Qualifiers on WMI Objects

A qualifier is a tag that provides additional information about a WMI object, method, or property.

To gain access to a WMI object's qualifiers

• Use the SWbemObject.Qualifiers_ property, as shown in the following sample.

  Set p = objMSS.Properties_(strProperty)
  
  If strNewValue <> "" Then
      'p is a MSS property variable
      p.Value = strNewValue
  Else
      d = p.Qualifiers_("DefaultValue")
      p.Value = d
  End If
  

Loading and Saving Configurations

To load values from a configuration file

• Use the VBScript Split function and FileSystemObject to parse the file and read property values, as shown in the following sample.

  Use the SWbemObjectProperties_ property to store the values read from the configuration file, and use the SWbemObjectPut_ method to update the server instance with those values.

  For Each line in Split(f.ReadAll, vbCrLf)
  
      ' Omit empty lines and comments
      ' ...
      ' Split line into name and value parts
      ' ...
  
          Set p = objMSS.Properties_(strName)
  
          If Not Err Then
  
              If p.IsArray Then
                  p.Value = Join(strValue)
              Else
                  p.Value = strValue
              End If
  
              If Err Then
                  WScript.Echo "Failed to assign " & strName & ": " & Err.Description : Err.Clear
              End If
  
          Else
              WScript.Echo "No such property: " & strName : Err.Clear
          End If
  Next
  
  ' Update WMI with modified instance
  objMSS.Put_
  

To save a server configuration to a file

1. Use the SWbemObjectProperties_ property to provide the collection of properties on the server, as shown in the following sample.

   Set fso = CreateObject("Scripting.FileSystemObject")
   Set f = fso.CreateTextFile(strFilename, true)
   
   ' Write all configuration settings
   For Each p In objMSS.Properties_
       If p.IsArray Then
           f.WriteLine p.Name & ":" & Join(p.Value)
       Else
           f.WriteLine p.Name & ":" & p.Value
       End If
   Next
   

2. Use the VBScript WriteLine method to write property values to a file.

See Also

Other Resources

Speech Server WMI Classes