Best way to handle exception in ADO.Net repository pattern

Question

i have design small repository pattern for ado.net. now i could not manage to handle exception proper way. i want to push error to calling environment if any occur. if no error occur then result set will be push to calling environment.

i have repository called AdoRepository which extend other repository classes like employee etc. we are calling employee repository function from mvc controller. so i want to push error to mvc controller from employee repository if any occur during data fetch, if no error occur then data will be sent to mvc controller. here is my full code. please have look and share the idea for best design. if possible paste rectified code here.

Base repository

 public abstract class AdoRepository<T> where T : class
    {
        private SqlConnection _connection;
        public virtual void Status(bool IsError, string strErrMsg)
        {

        }

        public AdoRepository(string connectionString)
        {
            _connection = new SqlConnection(connectionString);
        }

        public virtual T PopulateRecord(SqlDataReader reader)
        {
            return null;
        }

        public virtual void GetDataCount(int count)
        {

        }

        protected IEnumerable<T> GetRecords(SqlCommand command)
        {
            var reader = (SqlDataReader) null;
            var list = new List<T>();
            try
            {
                command.Connection = _connection;
                _connection.Open();
                reader = command.ExecuteReader();
                while (reader.Read())
                {
                    list.Add(PopulateRecord(reader));
                }

                reader.NextResult();
                if (reader.HasRows)
                {
                    while (reader.Read())
                    {
                        GetDataCount(Convert.ToInt32(reader["Count"].ToString()));
                    }
                }
                Status(false, "");
            }
            catch (Exception ex)
            {
                Status(true, ex.Message);
            }
            finally
            {
                // Always call Close when done reading.
                reader.Close();
                _connection.Close();
                _connection.Dispose();
            }

            return list;
        }

        protected T GetRecord(SqlCommand command)
        {
            var reader = (SqlDataReader)null;
            T record = null;

            try
            {
                command.Connection = _connection;
                _connection.Open();

                reader = command.ExecuteReader();
                while (reader.Read())
                {
                    record = PopulateRecord(reader);
                    Status(false, "");
                    break;
                }
            }
            catch (Exception ex)
            {
                Status(true, ex.Message);
            }
            finally
            {
                reader.Close();
                _connection.Close();
                _connection.Dispose();
            }
            return record;
        }

        protected IEnumerable<T> ExecuteStoredProc(SqlCommand command)
        {
            var reader = (SqlDataReader)null;
            var list = new List<T>();
            try
            {
                command.Connection = _connection;
                command.CommandType = CommandType.StoredProcedure;
                _connection.Open();
                reader = command.ExecuteReader();

                while (reader.Read())
                {
                    var record = PopulateRecord(reader);
                    if (record != null) list.Add(record);
                }
            }
            finally
            {
                // Always call Close when done reading.
                reader.Close();
                _connection.Close();
                _connection.Dispose();
            }
            return list;
        }
    }

StudentRepository which extend base AdoRepository
-----------------------------------------------
public class StudentRepository : AdoRepository<Student>
    {
        public int DataCounter { get; set; }
        public bool hasError { get; set; }
        public string ErrorMessage { get; set; }

        public StudentRepository(string connectionString)
            : base(connectionString)
        {
        }

        public IEnumerable<Student> GetAll()
        {
            // DBAs across the country are having strokes 
            //  over this next command!
            using (var command = new SqlCommand("SELECT ID, FirstName,LastName,IsActive,StateName,CityName FROM vwListStudents"))
            {
                return GetRecords(command);
            }
        }
        public Student GetById(string id)
        {
            // PARAMETERIZED QUERIES!
            using (var command = new SqlCommand("SELECT ID, FirstName,LastName,IsActive,StateName,CityName FROM vwListStudents WHERE Id = @id"))
            {
                command.Parameters.Add(new ObjectParameter("id", id));
                return GetRecord(command);
            }
        }

        public IEnumerable<Student> GetStudents(int StartIndex, int EndIndex, string sortCol, string sortOrder)
        {
            string strSQL = "SELECT * FROM vwListStudents WHERE ID >=" + StartIndex + " AND ID <=" + EndIndex;
            strSQL += " ORDER BY " + sortCol + " " + sortOrder;
            strSQL += ";SELECT COUNT(*) AS Count FROM vwListStudents";
            var command = new SqlCommand(strSQL);
            return GetRecords(command);
        }

        public override Student PopulateRecord(SqlDataReader reader)
        {
            return new Student
            {
                ID = Convert.ToInt32(reader["ID"].ToString()),
                FirstName = reader["FirstName"].ToString(),
                LastName = reader["LastName"].ToString(),
                IsActive = Convert.ToBoolean(reader["IsActive"]),
                StateID = Convert.ToInt32(reader["StateID"].ToString()),
                StateName = reader["StateName"].ToString(),
                CityID = Convert.ToInt32(reader["CityID"].ToString()),
                CityName = reader["CityName"].ToString()
            };
        }

        public override void GetDataCount(int count)
        {
            DataCounter = count;
        }

        public override void Status(bool IsError, string strErrMsg)
        {
            hasError = IsError;
            ErrorMessage = strErrMsg;
        }
}

calling StudentRepository from mvc controller like below way

 public class StudentController : Controller
    {
        private StudentRepository _data;

        public StudentController()
        {
            _data = new StudentRepository(System.Configuration.ConfigurationManager.ConnectionStrings["StudentDBContext"].ConnectionString);
        }

        // GET: Stuent
        public ActionResult List(StudentListViewModel oSVm)
        {

            StudentListViewModel SVm = new StudentListViewModel();
            SVm.SetUpParams(oSVm);
            SVm.Students = _data.GetStudents(SVm.StartIndex, SVm.EndIndex, SVm.sort, oSVm.sortdir).ToList();
            SVm.RowCount = _data.DataCounter;

            return View("ListStudents",SVm);
        }
    }

Answer 1

I don't get the point of this:

        catch (Exception ex)
        {
            Status(true, ex.Message);
        }

Simply not catch the exception and let it bubble up to the caller who, according to you, will know to handle it. No callbacks necessary.

Storing retrieved data in instance state seems like a bad way to go. Rather, return an object with that data. That results in a more straight forward API and has less mutable state.

---

        finally
        {
            reader.Close();
            _connection.Close();
            _connection.Dispose();
        }

There is a better way to go about this: Wrap resources in a using statement. In particular, part ways with the superstitious double dispose pattern.

Answer 2

Let the caller deal with the exception making sure that you log a decent error message (showing all relevant fields). The Status class will annoy the hell out of support people as it swallows the stack trace and says nothing about the data which has caused the error. DB exceptions are often caused by malformed data so its important to have this data logged when things go wrong.

As an aside, your PopulateRecord and GetDataCount methods should be abstract as the base versions do nothing. Another dev could easily think they don't need to implement these methods and would be left with a class with useless PopulateRecord and GetDataCount methods.