Windows Workflow Foundation is Framework for building the workflow enabled applications on windows. It consisting the workflow engine and designer. Workflow foundation supports both human and system workflow.
The Workflow Foundation can be used in the following scenarios
- Workflow within Line-of-business applications.
- User interface page flow
- Human workflow
- Workflow fro SOA applications
- Business rule driven workflow
Workflow foundation enables you to develop the applications with WCF and WPF technologies. Full support for VB.NET and C#, Debugging, a graphical designer for developing the workflow in code or markup.It also provides model and designer to build custom activities that encapsulate the workflow functionality for end users and can be reused across multiple projects.
A workflow is a set of activities which describes the process. It describes the short or long-running work.
Every workflow instance is created and maintained by an in-process engine referred as the workflow runtime engine. There can be multiple workflow runtime engines in an application.
Workflow model can be executed inside any windows process including console applications, forms-based applications, Windows services, ASP.NET Web sites and web services. Because a workflow is hosted in process, workflow can easily communicate with its host application.
Activities are elemental units in workflow. Activities are added to given flow path till it is completed then we say workflow instance is completed.
An activity can perform a single action, Example: writing a value to a database. It can be composite activity consist a set of activities. Activities have two types of behaviour design time and runtime.
WWF contains a library of standard activities and provides the mechanism for creating our own activity. This enables the extensibility and reusability between workflows.
This post explained the basic overview of workflow foundation and where can be it deployed. The coming posts discuss more in detail about the workflow foundation.