OLE Automation

OLE Automation (also sometimes referred to as Automation) is a Microsoft technology that allows one application to programmatically control another. It provides a mechanism for applications to expose their objects to other applications and tools. This exposure allows client applications to access and manipulate the functionality of server applications (also known as automation servers or components) as if they were local objects.

OLE Automation relies on the Component Object Model (COM) as its underlying architecture. COM defines a binary standard for components, enabling interoperability between applications written in different programming languages. An OLE Automation server exposes its functionality through a set of COM objects, each with its own properties and methods.

Client applications can access these objects and invoke their methods using a variety of programming languages and tools, including Visual Basic, C++, scripting languages (like VBScript and JavaScript), and macro languages within applications like Microsoft Office.

The process typically involves creating an instance of the server application's object, setting properties, and calling methods to perform specific tasks. This allows client applications to leverage the functionality of other applications to automate tasks, share data, and integrate different software systems.

While OLE Automation offers significant flexibility in application integration, it can also introduce dependencies between applications. Changes in the server application's object model can potentially break client applications that rely on it. Newer technologies, such as .NET Remoting and web services, have emerged as alternative approaches to application integration that address some of the limitations of OLE Automation. However, OLE Automation remains relevant for interacting with older applications and components that expose their functionality through COM.