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Object per workflow instance via Extension

Posted By:      Posted Date: October 02, 2010    Points: 0   Category :Windows Application

I have been trying unsuccessfully to create an extension that will allow me to supply a new instance of a object to each workflow instance.  Specifically, I am attempting to supply a variant of the UnitOfWork class used to managed long running NHibernate ISsessions.  I keep hearing that you can add a service behavior extension on a per-workflow instance basis, but none of the examples I’ve seen show you how.  When I attempt to retrieve the extension in my Activity, I always get the same singleton instance.


public class UnitOfWork : IUnitOfWork


        public Dictionary<string, ISessionFactory&

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Sharepoint Workflow - Object Reference Not Set to an instance of an object



I create a Custom Sharepoint workflow using VS 2008. Let me go step by step:

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Extension instance management for workflow service


I have written some custom activities for business validation (http://www.neovolve.com/post/2010/10/13/Custom-Workflow-activity-for-business-failure-evaluatione28093Wrap-up.aspx with project source at http://neovolve.codeplex.com/SourceControl/changeset/view/68064#1422354). They have worked fine until I use them in a workflow service.

The evaluator activity pushes a business failure into a custom extension. The custom extension will then detect whether the evaluator is contained in a scope activity. If there is a scope activity, it will store the failure in the extension for the scope to collect later. If there isn't a scope, it will throw an exception straight away. The scope will look for failures in the extension written by its child activities when it completes and will throw an exception for the set of failures.

This has worked fine so far for workflows executed via WorkflowInvoker and WorkflowApplication. There are unit tests for these activities to ensure that the above behavior is working as expected.

I have just used these activities in a workflow service and found that the extension behavior is very different. The function p

Visual Studio 2005 Extension for Sharepoint Workflow.


Hi All,

I want to develop sequential workflow using visual studio 2005. I have development server with Windows Server 2003 x86 installed.

Could anyone advise will i need to install Sharepoint first to have workflow feature in visual studio.

Also what all extension component i need to install to develop Sequential Workflow for Sharepoint 2007 document library.


Many Thanks


-- Regards Sandeep

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