I have been writing a series of posts recently about implementing a custom WF activity that will provide dependency resolution support for WF4 workflows.

The InstanceResolver activity caters for lazy loading dependencies, multiple resolutions on the one activity, workflow persistence (including support for non-serializable dependencies) and lifetime management of the resolved dependencies. The activity uses Unity as the backend IoC container however this could be modified to support a different container with minimal changes.

The following is a list of all the posts in this series.

• Dependency injection options for Windows Workflow 4 - Describes the options for getting dependencies into a workflow
• Custom Windows Workflow activity for dependency resolution–Part 1 - Outlines the design goals for the activity
• Custom Windows Workflow activity for dependency resolution–Part 2 - Provides the activity extension support for resolving dependencies
• Custom Windows Workflow activity for dependency resolution–Part 3 - Provides the implementation for the InstanceResolver activity
• Creating updatable generic Windows Workflow activities - A segue into an implementation for updatable generic typed arguments for generic activities
• Custom Windows Workflow activity for dependency resolution–Part 4 - Provides designer support with IRegisterMetadata and custom morphing
• Custom Windows Workflow activity for dependency resolution–Part 5 - Provides a custom updatable generic type argument support specific to the InstanceResolver activity
• Custom Windows Workflow activity for dependency resolution–Part 6 - Provides the XAML designer for the custom activity and a designer service for managing attached properties

This workflow activity and several others can be found in my Neovolve.Toolkit project which can be found here on Codeplex.