Notice (2018-05-24): bugzilla.xamarin.com is now in
Please join us on
Visual Studio Developer Community and in the
Mono organizations on
GitHub to continue tracking issues. Bugzilla will remain
available for reference in read-only mode. We will continue to work
on open Bugzilla bugs, copy them to the new locations
as needed for follow-up, and add the new items under Related
Our sincere thanks to everyone who has contributed on this bug
tracker over the years. Thanks also for your understanding as we
make these adjustments and improvements for the future.
Please create a new report on
GitHub or Developer Community with
your current version information, steps to reproduce, and relevant error
messages or log files if you are hitting an issue that looks similar to
this resolved bug and you do not yet see a matching new report.
In System.Data.SqlClient.SqlCommand class, the BeginExecuteInternal() method does not always return the IAsyncResult object.
If you use a stored procedure or a prepared statement, with CommantType.StoredProcedure the ar variable is not set as the result of onnection.Tds.BeginExecuteProcedure().
This crashes your application if you start using the SqlCommand by calling manually:
* EndExecuteNonQuery() which calls
* EndExecuteInternal() which calls
* Connection.Tds.WaitFor (sqlResult.InternalResult) where sqlResult.InternalResult is the set by BeginExecuteInternal() and is null if you use a stored procedure.
This throws a NullReferenceException
using(var cmd = new SqlCommand())
cmd.Connection = myConnection; // your connection
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = ""; // your procedure;
var res = cmd.BeginExecuteNonQuery();
This can easily be fixed by fixing https://github.com/mono/mono/blob/master/mcs/class/System.Data/System.Data.SqlClient/SqlCommand.cs#L849 and probably https://github.com/mono/mono/blob/master/mcs/class/System.Data/System.Data.SqlClient/SqlCommand.cs#L883 for prepared statments, assigning to ar the result of the call.
I tested and did a PR on github:
Mono 5.10 has significantly improved System.Data implementation which should resolve this issue. If you can still reproduce it please reopen the issue.