C#: Is this the correct way to use the SqlDataReader for DAAB

I have just started using the Data Access Application Block from microsoft. There are开发者_开发百科 very few instructions on the correct way to use the library. Just wanted to know if this is the correct way to use the data reader.

SqlDataReader reader = SqlHelper.ExecuteReader(config.ConnectionString, CommandType.Text, "select * from category");
List<string> a = new List<string>();
using (reader)
{
     while (reader.Read())
     {
          string t = reader.GetString(1);
          a.Add(t);
     }

     return a;
}

will everything get closed doing it this way? Is there any chance of memory leaks?

Put your reader initialization into the using block, and I would avoid using column numbers if you can, as they essentially turn into magic numbers. Unfortunately, that just requires you use the column names, but I have found that column names are less likely to change than column offsets, and you can always put your column names in a configuration file or something. Also, make sure you take into account the possibility for null columns

using(var reader = SqlHelper.ExecuteReader(etc. etc. etc.))
{
    while(reader.read()){
    {
        //Only need to do this if you don't want your string to be null
        //and if the "columnName" column is nullable.
        var stringValue = reader.IsDBNull(reader.GetOrdinal("columnName") 
                        ? "" 
                        : reader.GetString(reader.GetOrdinal("columnName"));
        a.Add(stringValue);
    }
}

HAve a look at

The Enterprise Library Data Access Application Block, Part 2