I'm working on a SharePoint project where several componenets (Workflow, List Definitions, Content Types, etc.) are tightly related to the same functionality. To reduce the risk of components breaking because of an out-of-sequence or missing dependency, and just to make things easier, I wanted to throw everything together in the same project. I discovered something interesting about Workflows in the process, however.

Namely, if you try to add a Workflow to a typical project, you'll get an error in the Workflow designer saying:

     "The service 'System.Workflow.ComponentModel.Compiler.ITypeProvider' must be installed for this operation to succeed."

This happens if you added references to the proper assemblies (System.Workflow.Activities, System.Workflow.ComponentModel, System.Workflow.Runtime and microsoft.sharepoint.WorkflowActions)!

Odd, but luckily there are solutions. One is to write a bunch of code to build the support that the Workflow Designer needs, but I was looking for something even simpler. What I discovered, is that you can add support for Workflows to your project (the .csproj or .vbproj file) by cracking it open in notepad and adding some "ProductTypeGuids" to the project XML. Just add both of the GUIDs featured in the ProjectTypeGuids element below (or add the element if it's not there), and you should be good to go!

 I'm curious to see if you can add these GUIDs to many types of projects to enable Workflow support (and further curious about if there are any consequences apart from designer support),

A collegue of mine recently asked a fairly common question for SharePoint developers getting familiar with the SharePoint API; "If I have the absolute URI of my web, how do I use it to instantiate a corresponding SPWeb object?"

You'd assume that the SPWeb would have a constructor that accepts an absolute URI, but that isn't the case. What you have to do is first create an SPSite using your URI, then call the parameterless OpenWeb() method on it.

I got this information through the grapevine. For those using the latest version of the .NET Framework and/or SQL Server 2008, but using the older version of Windows SharePoint Services, this is pretty important.