I want use document review and approval process using DotCmis but how i can use this in c#.
how will i impliment .
The CMIS spec does not include workflows. You may use Webscript/REST API. You can also check this:
CMIS and workflows
cmis specification has no support for workflow. So, you will not find anything related to workflow in dotcmis or opencmis.
alfresco - CMIS integration with BPM - Stack Overflow
You can create some specific spaces in your repository that allow you to manage your workflows.
Consider the space as an operator and the interaction with the space could be a content dropped inside one of them.
For example you can create a dedicated tree in your repository for managing your workflow: a main space Workflow X with some children spaces such as Approve, Reject or Loop and so on.
Notice that you can attach a rule with some actions to an Alfresco space and if you consider the execute-script action, it could be the right way to follow for managing a workflow in a transparent way.
In this way you can use any of the Alfresco APIs exposed (FTP, CMIS, REST/WebScripts, WebDAV) for interacting with workflows simply creating, moving or deleting content inside your spaces.
Considering to drop content such as CSV or XML that allow you to read using an action with a rule and then get all the metadata you need to managing your own workflows.
Hope this helps
Retrieving data ...