public int StartDBListening(string query, OnChangeEventHandler func)
{
int result = -1;
OracleCommand cmd = null;
try
{
if (ConnectionOpen())
{
cmd = new OracleCommand(query, _Connection);
cmd.AddRowid = true;
//OracleDependency dep = new OracleDependency(cmd);
dep.AddCommandDependency(cmd);
cmd.Notification.IsNotifiedOnce = false;
bool buldu = false;
foreach (var item in dep.RegisteredResources)
{
if (item.ToString() == query)
{
buldu = true;
}
}
if (buldu == false)
{
dep.OnChange += new OnChangeEventHandler(func);
}
cmd.ExecuteNonQuery();
}
}
catch (OracleException oex)
{
}
catch (Exception ex)
{
LogIslemleri.LogYaz(ex.Message);
result = -1;
}
finally
{
if (cmd != null)
{
cmd.Dispose();
}
CloseConnection();
}
return(result);
}
public Task StartListener() => Task.Run(() =>
{
var dependency = new OracleDependency
{
QueryBasedNotification = false
};
dependency.OnChange += this.OnNotification;
var conn = this.CreateConnection();
var cmd = conn.CreateCommand();
dependency.AddCommandDependency(cmd);
cmd.CommandText = "SELECT * FROM CHATS";
cmd.AddRowid = true;
cmd.Notification.IsNotifiedOnce = false;
cmd.ExecuteNonQuery();
});
/// <summary>Инициализирует процесс отслеживания изменений в БД</summary>
private void InitNotifier()
{
NotifierConnection = new OracleConnection(ConnectionString);
NotifierConnection.AutoCommit = false;
NotifierConnection.Open(); // открываем постоянное соединение с БД
// подписываемся на получение информации об обновлениях таблиц
Notifier = new OracleDependency();
Notifier.QueryBasedNotification = false;
Notifier.OnChange += Dependency_OnChange;
StringBuilder SQLText = new StringBuilder();
for (int i = 0; i < SharedDataInfo.Tables.Length; i++)
{
SQLText.AppendFormat("select 1 from {0} where 1=0", SharedDataInfo.Tables[i]);
if (i != SharedDataInfo.Tables.Length - 1)
SQLText.Append(" union all ");
}
NotifierCommand = NotifierConnection.CreateCommand(SQLText.ToString());
Notifier.AddCommandDependency(NotifierCommand);
ConfigureCommand(NotifierCommand);
NotifierCommand.ExecuteReader();
NotifierCheckThread = new Thread(CheckNotifier);
NotifierCheckThread.IsBackground = true;
NotifierCheckThread.Start();
Log.Message("Поток контроля нотификатора запущен. ThreadID: {0}", NotifierCheckThread.ManagedThreadId);
}
