Question

I am trying to come up myself with an acceptable pattern for data reading from DB using Enterprise Library. How do you consider the following pattern (I mean, the null-check in the finally block)?

IDataReader NewReader = null;

try
{
    NewReader = (SqlDataReader)(SqlDatabase.ExecuteReader(SqlCommand));

    /* Do some work with NewReader. */

    NewReader.Close();
}
catch /* As much 'catch' blocks as necessary */
{
    /* Handle exceptions */
}
finally
{
    if (!ReferenceEquals(NewReader, null))
    {
        NewReader.Dispose();
    }
}

Is this null-check acceptable, or is there a more elegant way of solving this problem?

Answer 1

I would use if(NewReader == null). It’s the default way of checking for null. Your way of doing it is the same, but it looks strange and thus might confuse people.

Besides: Why don’t you use using? Makes your code a lot cleaner:

try
{
    using(IDataReader NewReader = (SqlDataReader)(SqlDatabase.ExecuteReader(SqlCommand)))
    {
        /* Do some work with NewReader. */
    }
}
catch /* As much 'catch' blocks as necessary */
{
    /* Handle exceptions */
}