For this same purpose, The Microsoft Data Access block checks to see if the
transaction.connection is a valid connection or null.

- Sahil Malik
http://dotnetjunkies.com/weblog/sahilmalik

You can examine the @@trancount.  If it is > 0 then the transaction is
active.  Otherwise the transaction has been rolled back.

 new SqlCommand("select @tc = @@trancount)

and bind an output parameter to @tc.

David

the commit will fail if no pending transaction exits - this will be your
fallback.

procs generally test @@trancount to avoid throwing an error on rollback when
there is no nested transction. you need to look to see how the proc is
returning failure - return value, raiserror, or paramter.

you are going to use multiple batches be sure to use the same connection,
and don't close it. at anytime you can select @@trancount to see a
transaction is active. you could also use the follow sp to do the commit.

   create proc DoCommit as
   set nocount on
   if @@trancount > 0
   begin
       commit tran
       select 1 as CommitResult
   end
   return 0 as CommitResult

then use

   cmd = new SqlCommand("DoComitt", connection);
   cmd.CommandType = CommandType.StoredProcedure;
   bool  ok = ((int) cmd.ExecuteScaler()) ==1);

-- bruce (sqlwork.com)