确定Linq to Sql查询的源DataContext

In my application I have several DataContexts that connects to different databases with different schemas. In a custom user control I display the results of the query and let the user edit them, and when the user edits the data I want to persist the changes to the database. To do that I need a reference to the source DataContext (or at least the source datacontext type) so I can do a In my application I have several DataContexts t