|
|
Rank: Administration
Groups: Administration
Joined: 6/20/2008
Posts: 612
Location: Cheshire, United Kingdom.
|
For the first part of a series of AFSDK tips, we will show you how to connect to an AF server using the AFSDK that is supplied with PI-AF v 1.3x - note, code to achieve this is version 2 will follow shortly.
Using Visual Studio.Net create a new project (windows form is fine) and add 3 references to:
- OSISoft.PI.System
- OSISoft.PI.Modeling
- OSISoft.PI.UnitsOfMeasure
Then import the namespaces into your form class:
Code:Imports OSIsoft.PI
Imports OSIsoft.PI.Modeling
Imports OSIsoft.PI.UnitsOfMeasure
Next create two class level variables, one to hold the AFDatabase object and the other to hold the AFModelFramework object:
Code:Private AFDB As AFDatabase
Private AFSS As AFModelFramework
Now within our form load routine (or any routine of your choice) we create an instance of the "PISystems" class and attach our AFSS object to the Modeling subsystem of the PISystem.
Code: Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Try
Dim PISys As New PISystems
AFSS = CType(PISys("piservername").SubSystems("Modeling"), AFModelFramework)
If (AFSS Is Nothing) Then
' NO MODELING SUBSYSTEM AVAILABLE?
Exit Sub
End If
Catch ex As Exception
' ERROR GETTING SUBSYSTEM
End Try
End Sub
Once we are connected to the Modeling SubSystem, we assign our AFDB object to the required database on the AF Server.
Code: Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Try
Dim PISys As New PISystems
AFSS = CType(PISys("piservername").SubSystems("Modeling"), AFModelFramework)
If (AFSS Is Nothing) Then
' NO MODELING SUBSYSTEM AVAILABLE?
Exit Sub
End If
AFDB = AFSS.Databases("afdatabasename")
If (AFDB Is Nothing) Then
' NO DATABASE IS AVAILABLE?
Exit Sub
End If
Catch ex As Exception
' ERROR GETTING SUBSYSTEM
End Try
End Sub
And there you have it, connecting to an AF database using the AFSDK!Principal Consultant
Real-Time Data Management @ Wipro Technologies
|
|
|
|
|
OSIsoft vCampus is a subscription-based, online offering that consists of providing everything people need to develop applications on the PI System. We invite you to take a "tour" of the OSIsoft Virtual Campus - also feel free to consult the FAQ or contact OSIsoft vCampus for more details.
|
|
|
Rank: Administration
Groups: Administration
Joined: 6/20/2008
Posts: 612
Location: Cheshire, United Kingdom.
|
Create this as a reusable connection method for your custom applications and you could end up with something similar to this:
Code: Private PISys As PISystems
Private AFDB As AFDatabase
Private AFSS As AFModelFramework
Private Function ConnectToAF(ByVal WhichPISystem As String, ByVal WhichDatabase As String) As Boolean
Dim ret As Boolean = False
Try
' Check PISystems object, create if required
If (PISys Is Nothing) Then PISys = New PISystems
' Check AFModelFramework object, create if required
If (AFSS Is Nothing) Then AFSS = CType(PISys(WhichPISystem).SubSystems("Modeling"), AFModelFramework)
' If object already existed, check it is set to correct PI System
If Not AFSS.PISystem.Name.ToLower.Equals(WhichPISystem.ToLower) Then AFSS = CType(PISys(WhichPISystem).SubSystems("Modeling"), AFModelFramework)
' AFModelFramework now exists, so check AFDatabase object, create if required
If (AFDB Is Nothing) Then AFDB = AFSS.Databases(WhichDatabase)
' If object already existed, check it is set to correct AF Database
If Not AFDB.Name.ToLower.Equals(WhichDatabase.ToLower) Then AFDB = AFSS.Databases(WhichDatabase)
' Final checks to see if AF is connected
ret = (Not (AFSS Is Nothing)) And (Not (AFDB Is Nothing))
Catch ex As Exception
ret = False
End Try
Return ret
End Function
And to use this you would call:
Code: If ConnectToAF("af_server_name", "af_database_name") Then
End If
Principal Consultant
Real-Time Data Management @ Wipro Technologies
|
|
|
|
Guest
|
