Where is Windows Workflow Foundation used?

Question

Is WF used at user interface or business layer? If at UI layer, then does someone coding in business layer even need to use or learn it?

Answer 1

Chris offered a great answer, so I'll take a different tack. Workflow is really not the same as logic. Workflows are generally compositions of logic, which makes them a complimentary contributor to the whole. Where a business component nicely encapsulates a single piece of business rules or behavior, a workflow composes multiple business components, rules, and behavior to meet the needs of larger, longer-running business processes.

Workflows can fit anywhere, filling process needs for UI, business, and even data layers. If you do end up using WF, I highly recommend that you train your general development staff, so that there is broad knowledge and understanding. Despite having a visual aspect to it, WF still requires some low-level coding to build up a library of activities and such that workflow creators and maintainers will use.

EDIT:

Its up to you whether to use it or not. Generally, WF is used by larger projects, because WF offers a valuable return on investment. WF is harder to use than simply writing code. There is a fairly steep learning curve, requires a different way of approaching business problems, and requires special skill sets. Providing code to WF adds overhead, as you have to write activities that may be used in workflows, as well as build the workflows themselves.

If you think that using WF for your small project will provide a valuable return on investment, then go for it. You will need to both recoup the initial costs of training, infrastructural implementation, and deployment, as well as providing long-term, tangible cost savings over simply writing code to solve the problems at hand. I would be doubtful that WF will offer a small project such ROI. For larger projects, or multiple integrated projects for a single large company, it is much easier to realize that ROI than it is with smaller projects, which is why workflow platforms like WF are usually only used on that scale.

Answer 2

WF is the interface to the buisness layer.

Workflows are a declarative way of writing programs by linking together pre-defined activities rather than an imperative programming model of writing lines of code. IN addition, you have many graphical tool that allow you to wrtie workflows. shuch as black pearl, K2 and sharepoint designer.

They are very much used and are well worth learning. I started using then in sharepoint and ms crm. I now always look to workflows to solve my common problems.

here are a few links: mirosoft msdn.microsoft.com/en-us/netframework/default.aspx Wkik: http://en.wikipedia.org/wiki/Windows_Workflow_Foundation