How to suspend workflow and resume workflow?

I have long running workflow; and I want to give user option to suspend开发者_运维问答 workflow and resume it when he is ready...

How can I achieve this in wf4 ?

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WF4 uses Bookmarks now, suspend and unsuspend is only working in wf3.

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There's a video and sample code from MSDN which show how to do it.

This presumes you're using the AppFabric host. You may be able to port the idea to a non-AppFabric workflow if need be.