/// <summary>
/// Constructor containing a <see cref="DALCTransaction"/> for data access logic component(s) that
/// need to participate in a transaction.
/// </summary>
/// <param name="transaction">The <see cref="DALCTransaction"/> to be used for this data operation.</param>
protected CommonDALC(DALCTransaction transaction)
{
// Assign the DALCTransaction object
_transaction = transaction;
// Set in transaction flag. The IDbTransaction may be null if the BusinessFacade was
// instantiated to not do transactioning. A DALCTransaction is still created, just
// without the inner IDbTransaction.
if (transaction == null || transaction.GetTransaction() == null)
{
_isInTransaction = false;
}
else
{
_isInTransaction = true;
}
}
/// <summary>
/// This method executes a query against the database and returns the results as a
/// <see cref="DataTransferObject"/>. The primary purpose of this method is to retrieve
/// a single entity (record) from the database (master) that may have associated child
/// records (details).
/// </summary>
/// <param name="helper">The <see cref="DALCHelper"/> class that contains the database
/// command information.</param>
/// <param name="criteria">The <see cref="DataTransferObject"/> containing the criteria
/// to be used to determine mathing records in the database.</param>
/// <returns>The <see cref="DataTransferObject"/> now populated with the record found
/// in the database matching the specified criteria.</returns>
protected DataTransferObject ExecuteQueryDto(DALCHelper helper, DataTransferObject criteria)
{
// Initialize objects
IDataReader reader = null;
Database db = null;
DbCommandWrapper cw = null;
// Initialize output parameters
DataTransferObject dto = null;
// If the passed in helper is null throw exception
if (null == helper)
{
throw new MNNonFatalException("CommonDALC.ExecuteQueryDto was passed a null DALCHelper.");
}
// Make sure any necessary criteria has been set
if (helper.CriteriaIsValid(criteria) == false)
{
throw new MNNonFatalException("CommonDALC.ExecuteQueryDto was passed invalid search criteria.");
}
try
{
// Initialize the database and command wrapper
if (helper.DbInstanceName() == null)
{
db = DatabaseFactory.CreateDatabase();
}
else
{
db = DatabaseFactory.CreateDatabase(helper.DbInstanceName());
}
cw = helper.InitializeCommand(db, criteria);
DbCommand command = cw.Command;
// Execute a data reader
if (_isInTransaction)
{
reader = db.ExecuteReader(command, _transaction.GetTransaction());
}
else
{
reader = db.ExecuteReader(command);
}
// set command for garbage collection
command = null;
// Convert the results into a data transfer object
dto = helper.ConvertResultsDto(cw, reader);
}
catch (MNException e)
{
e.AddMessageTraceData("MNException caught in CommonDALC.ExecuteQueryDto");
throw;
}
catch (Exception e)
{
MNException ex = new MNException(e.Message, e, criteria);
ex.AddMessageTraceData("Exception caught in CommonDALC.ExecuteQueryDto");
throw ex;
}
finally
{
// Close the data reader if it has not already been closed
if ((null != reader) && (reader.IsClosed == false))
{
reader.Close();
}
// Set the database object for garbage collection
if (db != null)
{
db = null;
}
// Set the command wrapper object for garbage collection
if (cw != null)
{
cw = null;
}
}
// Return the data transfer object
return(dto);
}