private bool ReadMessageBatch(SqlConnection connection)
{
if (SupportsNotify)
{
return(ReadNotifyMessages(connection));
}
var messages = new EventMessages();
using (var command = new SqlCommand(Sql.GetMessageRange, connection))
{
command.CommandType = CommandType.StoredProcedure;
// The stored procedure takes a time (in ticks) as parameter instead of message ID, because
// messages in the database are not necessarily ordered by ID.
command.Parameters.Add("@fromTime", SqlDbType.BigInt).Value = _lastReadMessageTime;
command.Parameters.Add("@afterSequence", SqlDbType.Int).Value = _lastReadMessageSequence;
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
_lastReadMessageTime = reader.GetInt64(1);
_lastReadMessageSequence = reader.GetInt32(2);
var time = new System.DateTime(_lastReadMessageTime);
string exceptionXml = (reader.IsDBNull(8) ? null : reader.GetString(8));
var message = new SqlEventMessage(this, reader.GetInt32(0),
reader.GetString(4), reader.GetString(3), reader.GetString(5), reader.GetString(6),
reader.GetString(7), time, exceptionXml);
message.Intern(_interner);
SetMessageSequence(message, _lastReadMessageSequence);
messages.Add(message);
}
}
}
// Note that the messages don't have parameters or details at this stage - those will be read as needed.
if (messages.Count > 0)
{
_raiseExistingRead = true; // We have more messages.
HandleEventMessages(messages);
return(true);
}
if (_raiseExistingRead)
{
_raiseExistingRead = false; // Don't raise again until we've read some messages.
OnExistingMessagesRead(System.EventArgs.Empty);
}
return(false);
}
private SqlEventMessage ReadMessage(IDataRecord reader)
{
var time = new System.DateTime(reader.GetInt64(1));
string exceptionXml = (reader.IsDBNull(8) ? null : reader.GetString(8));
var message = new SqlEventMessage(this, reader.GetInt32(0),
reader.GetString(4), reader.GetString(3),
reader.GetString(5), reader.GetString(6),
reader.GetString(7), time, exceptionXml);
message.Intern(_interner);
SetMessageSequence(message, reader.GetInt32(2));
return(message);
}
protected override void ReadAll()
{
var messages = new EventMessages();
using (var connection = new SqlConnection(_connectionString))
{
connection.Open();
using (var command = new SqlCommand(Sql.GetAllMessages, connection))
{
command.CommandType = CommandType.StoredProcedure;
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
var time = new System.DateTime(reader.GetInt64(1));
string exceptionXml = (reader.IsDBNull(8) ? null : reader.GetString(8));
var message = new SqlEventMessage(null, reader.GetInt32(0),
reader.GetString(4), reader.GetString(3), reader.GetString(5), reader.GetString(6),
reader.GetString(7), time, exceptionXml);
message.Intern(_interner);
SetMessageSequence(message, reader.GetInt32(2));
messages.Add(message);
}
}
}
// Read the parameters immediately.
foreach (SqlEventMessage message in messages)
{
message.SetParameters(ReadParameters(connection, message.Id));
}
}
if (messages.Count > 0)
{
HandleEventMessages(messages);
}
}
