How To Use the Shared Property Manager in MTS Through VB Code

MORE INFORMATION

The are three basic steps in this article:

1. Create the Visual Basic ActiveX DLL which will contain the methods that set and retrieve the SPM property.
2. Create a simple client that will access this component.
3. Install the component into MTS.

NOTE: This article assumes that the development of the component and client mentioned above will be done on the same machine as MTS.

Step 1: Create the ActiveX DLL

1. Create a new Visual Basic ActiveX DLL project.
2. From the Project menu, choose Project Properties. On the General tab, change the project name to "SPMSample," check the Unattended Execution box, and make sure the threading model is set to Apartment Threading.
3. From the Project menu, choose References. Add a reference to Microsoft Transaction Server Type Library and Shared Property Manager Type Library.
4. Add the following code to the default class:

         Option Explicit
   
         Public Function GetSPM(ByVal szGroup As String, _
                                 ByVal szProperty As String) _
                                 As String
   
             On Error GoTo ErrHandler
   
             Dim ctxObject As ObjectContext
             Dim spmMgr As SharedPropertyGroupManager
             Dim spmGroup As SharedPropertyGroup
             Dim spmProp As SharedProperty
             Dim bGroupExists As Boolean
             Dim bPropExists As Boolean
   
             Set ctxObject = GetObjectContext()
   
             Set spmMgr = CreateObject _
                 ("MTxSpm.SharedPropertyGroupManager.1")
   
             'OPTIONS
             '-------------------------------------------------
             'LockSetGet (0)  = Locks the particular property
             '                   while it is being set
             'LockMethod (1) = Locks all of the properties
             '                   in the property group
             '                   until the method is complete
             '
             'Standard (0) = Destroys property when all
             '               clients have released there reference
             'Process (1) = The property group is not destroyed
             '               until the process in which it lives
             '               is terminated.
             '
             'NOTE: If debugging these from within the VB 5.0 IDE
             'then you will need to use LockSetGet.  LockMethod
             'requires that the object have an ObjectContext
             '-------------------------------------------------
             'Set spmGroup = spmMgr.CreatePropertyGroup _
                 (Trim(szGroup), LockSetGet, Process, bGroupExists)
             Set spmGroup = spmMgr.CreatePropertyGroup _
                 (Trim(szGroup), LockMethod, Process, bGroupExists)
             Set spmProp = spmGroup.CreateProperty _
                 (Trim(szProperty), bPropExists)
   
             If bPropExists = False Then
                 GetSPM = "Property Does Not Exist"
             Else
                 GetSPM = spmProp.Value
             End If
   
             ctxObject.SetComplete
             Exit Function
   
         ErrHandler:
   
             If Not ctxObject Is Nothing Then
                 ctxObject.SetAbort
             End If
             GetSPM = "Error Occurred"
             Err.Raise Err.Number, "", Err.Description, ""
             Exit Function
   
         End Function
   
         Public Sub SetSPM(ByVal szGroup As String, _
                             ByVal szProperty As String, _
                             ByVal szValue As String)
   
             On Error GoTo ErrHandler
   
             Dim ctxObject As ObjectContext
             Dim spmMgr As SharedPropertyGroupManager
             Dim spmGroup As SharedPropertyGroup
             Dim spmProp As SharedProperty
             Dim groupExists As Boolean
             Dim propExists As Boolean
   
             Set ctxObject = GetObjectContext()
   
             'Create an instance of the SPM.  Retrieve the
             'group and property and then set the value
             '-------------------------------------------------
             Set spmMgr = CreateObject _
                 ("MTxSpm.SharedPropertyGroupManager.1")
             Set spmGroup = spmMgr.CreatePropertyGroup _
                 (Trim(szGroup), LockSetGet, Process, groupExists)
             'Set spmGroup = spmMgr.CreatePropertyGroup _
                 (Trim(szGroup), LockMethod, Process, groupExists)
             Set spmProp = spmGroup.CreateProperty _
                     (Trim(szProperty), propExists)
   
             spmProp.Value = szValue
   
             ctxObject.SetComplete
             Exit Sub
   
         ErrHandler:
   
             If Not ctxObject Is Nothing Then
                 ctxObject.SetAbort
             End If
             Err.Raise Err.Number, "", Err.Description, ""
             Exit Sub
   
         End Sub
   
   						

Step 2: Create the Client Application

1. Create a new Visual Basic Standard EXE file. Form1 is created by default.
2. On the default form, add one Label, one Text Box, and two CommandButtons.
3. Add the following code to the default form:

         Private Sub Command1_Click()
   
             Dim obj As Object
             Dim szGroup As String
             Dim szProperty As String
             Dim szValue As String
   
             szValue = Trim(Text1.Text)
   
             szGroup = "TestGroup"
             szProperty = "TestProperty"
             Set obj = CreateObject("SPMSample.Class1")
   
             obj.SetSPM szGroup, szProperty, szValue
   
             Set obj = Nothing
   
         End Sub
   
         Private Sub Command2_Click()
   
             Dim obj As Object
             Dim szGroup As String
             Dim szProperty As String
             Dim szValue As String
   
             szValue = Trim(Text1.Text)
   
             szGroup = "TestGroup"
             szProperty = "TestProperty"
             Set obj = CreateObject("SPMSample.Class1")
   
             Label1.Caption = obj.GetSPM(szGroup, szProperty)
   
             Set obj = Nothing
   
         End Sub
   
         Private Sub Form_Load()
   
             Command1.Caption = "Set SPM Value"
             Command2.Caption = "Retrieve SPM Value"
   
         End Sub
   
   						

Step 3: Install the Component into MTS

1. Start the Microsoft Management Console (MMC), Transaction Server Explorer.
2. Using the Tree View in the left-hand pane, expand "Computers," then "My Computer," and then the "Packages Installed" node.
3. Right-mouse click the Packages Installed icon and choose "New," and then "Package."
4. Choose to create and empty package. Name the package "SPMSample" and have it run as the interactive user.
5. Select the Components folder under the newly-created package, right- mouse click and choose "New," and then choose "Component."
6. Choose 'Import component(s) that are already registered' and choose SPMSample.Class1 from the list that is displayed.

You should now be able to run your client application and set and retrieve the Shared Property Manager value.

NOTE: It is assumed here that the client will be run on the same machine as MTS.