Why call SqlClient.SqlDataReader Close() method anyway?

Question

Is the SqlClient.SqlDataReader a .NET managed object or not? Why do we have to call the Close() method explicitly close an open connection? Shouldn\'t running out of scope f

Answer 1

@Lieutenant Frost

As a rule in our shop, we explicitly wrap all database calls in a Try...Finally block, with the finally section catching and closing the data connections. It's worth the tiny bit of effort to save yourself a major troubleshooting headache.

I have a similar rule, but I require that objects implementing IDisposable use the 'using' block.

using (SqlConnection conn = new SqlConnection(conStr))
{
     using (SqlCommand command = new SqlCommand())
     {
        // ETC
     } 
}

The using block calls Dispose immediately when leaving the scope, even with an exception.

Answer 2

Also take into consideration what happens when an exception gets thrown - you never know if the connection will be closed if you suddenly are forced out of the executing code.

As a rule in our shop, we explicitly wrap all database calls in a Try...Finally block, with the finally section catching and closing the data connections. It's worth the tiny bit of effort to save yourself a major troubleshooting headache.