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OSIsoft, LLC


The AF SDK is a Microsoft .NET based programmatic library that provides structured access to the variety of data stored in the OSIsoft PI System. This data includes:

  • Assets and their properties and relationships
  • Time Series data from the PI Data Archive and other sources
  • Event frames that record and contextualize process events

The AF SDK is designed for easy access from Microsoft .NET languages like Visual Basic .NET (VB.NET), C#, and Managed C++. The AF SDK is available for .NET 3.5 and .NET 4.6.2 Frameworks and targets Any CPU so that it is available for both 32-bit and 64-bit Windows operating systems.

The AF SDK presents a hierarchical model of objects and collections that represent underlying OSIsoft features and concepts. Programs typically start by obtaining one or more PISystem objects. The PISystem object can then be used to search for objects, add new objects, modify existing objects, or remove objects in the server. The Namespaces section provides documentation of the objects and example code that shows how to program with the object in Visual Basic .NET and C#.

The AF SDK is not limited to only interacting with the AF Server. It provides rich, powerful methods to interact directly with the PI Data Archive and is almost always more appropriate to use than the older PI SDK. The AF SDK data access methods in the OSIsoft.AF.Data namespace and the OSIsoft.AF.PI namespace supersede the functionality provided by PI SDK. Though the PI SDK is still available, it is more appropriate to use AF SDK than the PI SDK, except in architecture that demands only native code.

AF SDK Library Reference
Version 2.10.0

The What's New page will provide an overview of recent changes in the AF SDK Library.

The following high-level hierarchy diagrams will provide an overview of each area within the library.

Enabling Operational Intelligence