When the user clicks the Received button, we can create a reference to the Transaction Server object that we have created by using the code snippets that we saw earlier, and can display for the user the resulting in stock and back order amounts with the code in Listing 28.5.
Listing 28.5 - RECVNG.FRM - The method used to create a reference to our Transaction Server object, and call the method that we created in the object.
Private Sub cmdReceived_Click() Dim iBackOrder As Integer Dim iCurInventory As Integer Dim ProgID As String Dim obj As Object 'Set up the error handling On Error GoTo ErrorHandler 'Decide which component to use ProgID = "InvMaint.InvMnt" 'Create the appropriate object Set obj = CreateObject(ProgID) 'Were we able to create the object? If obj Is Nothing Then MsgBox "Create object " + ProgID + "failed." Exit Sub End If 'Call the object method If obj.ChangeInv(iiProductID, CLng(txtCount.Text), iBackOrder, _ iCurInventory) = -1 Then Err.Raise ERROR_NUMBER End If 'Release the object Set obj = Nothing 'Display for the user what the current inventory is MsgBox "New Inventory received, current backorder count = " _ + Str$(iBackOrder) + " and current inventory = " _ + Str$(iCurInventory) Exit Sub ErrorHandler: 'Show the user the error message MsgBox "Error " + Str$(Err.Number) + " : " + Err.Description Exit Sub End Sub
Before we run our form, let's change the view in the Transaction Server Explorer to show the status of our object. We do this by selecting the Components folder in the package we have created. Next, choose View, Status. The right side of the Explorer will now show us the activity status of our object. If you run the form with the Transaction Server Explorer where it can be seen, you can watch as the object that we created earlier is instantiated and executed, as seen in Figure 28.23.
When the form that we have created calls the object that we registered in Transaction Server, you can see as the object is created and run.