Create a web application to access data through AF

Discussion created by AlistairFrith on Apr 7, 2011
Latest reply on Apr 18, 2011 by andreas

I am new to web coding so please forgive if I have made any fundamental mistakes here!


I am trying to create a Web application to display PI data (without uwing Sharepoint and WebParts). At the moment, I have a simple 'Hello World' ASP .NET Web Application, built in Visual Studio 2008, that has a label which is filled in in the Page_Load event handler.


To start off, I wanted to connect to our AF Server and display its DB name, then work towards getting eement and attribute data etc. So here is my code:


using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using OSIsoft.AF;

namespace PIWebApp
    public partial class _Default : System.Web.UI.Page
        PISystems af ;
        PISystem mySystem;
        AFDatabase myDatabase;

        protected void Page_Load(object sender, EventArgs e)
            af = new PISystems();
            mySystem = af["LIMES"]; //TODO: Must change to your AF server
            myDatabase = mySystem.Databases["Configuration"]; //TODO: Must change to your AF database

            Label1.Text = "Hello World. My AF DB is called " + myDatabase.Name;



The AF-related code is lifted directly from a Windows .NET application that works. But when I run this, it fails.'af' is initialised ok and so is 'mySystem', but its 'Databases' collection contains no objects and assigning myDatabase to "Configuration" brings up a dialog looking for PISystem.cs.


Any ideas?


--- Alistair.