Question

This is my aspx code when i want to fetch just one record.

            conn = new SqlConnection(cs);
            string sql = "SELECT * FROM [school_database].[arrest_school].[registration_allstudent] where RegistrationId='llts4da2'";
            SqlCommand cmd = new SqlCommand(sql, conn);
            conn.Open();
            reader = cmd.ExecuteReader();
            reader.Read();
            Model.Registration regis = new Model.Registration();
            regis.Address = reader["Address"].ToString();
            return regis;

Now i want to fetch all the records and return regis array. How to do it.
I know how to count the row in read and then how to fill it regis array.
Regis has 5 fields…Address, city, name, class, phoneno

Answer 1

To read all the records, one way is this:

using(IDataReader reader = cmd.ExecuteReader())
{
    List<Registration> result  = new List<Registration>();
    while(reader.Read())
    {
        result.Add(new Registration{Address=reader["Address"].ToString()});
    }
    return result;
}

Another way is this:

DataTable t = new DataTable();
t.Load(cmd.ExecuteReader);
var result  = from c in t.AsEnumerable()
              select new Registration{Address=c.Field<string>("Address")};
return result.ToList();