create table tab_cn(id number, val number);insert into tab_cn values(1,100);
insert into tab_cn values(2,200);
insert into tab_cn values(3,300);
commit;SQL> select t.*, rowid from morven.tab_cn t;ID        VAL ROWID
---------- ---------- ------------------1       100  AAAarDAAKAADEmFAAA2        200 AAAarDAAKAADEmFAAB3        300 AAAarDAAKAADEmFAAC

grant change notification to morven;

OracleDependency dep;
OracleConnection conn;
//
public MainWindow()
{InitializeComponent();//设置App的监听端口，即使用哪个端口接收Change Notification。
    OracleDependency.Port = 49500;string cs = "User Id=morven;Password=tr;Data Source=mh";conn = new OracleConnection(cs);conn.Open();
}
//
private void btReg_Click(object sender, RoutedEventArgs e)
{
OracleCommand cmd = new OracleCommand("select * from tab_cn", conn);
//绑定OracleDependency实例与OracleCommand实例
dep = new OracleDependency(cmd);
//指定Notification是object-based还是query-based，前者表示表（本例中为tab_cn）中任意数据变化时都会发出Notification；后者提供更细粒度的Notification，例如可以在前面的sql语句中加上where子句，从而指定Notification只针对查询结果里的数据，而不是全表。
dep.QueryBasedNotification = false;
//是否在Notification中包含变化数据对应的RowId
dep.RowidInfo = OracleRowidInfo.Include;
//指定收到Notification后的事件处理方法
    dep.OnChange += new OnChangeEventHandler(OnNotificaton);//是否在一次Notification后立即移除此次注册
cmd.Notification.IsNotifiedOnce = false;
//此次注册的超时时间（秒），超过此时间，注册将被自动移除。0表示不超时。
cmd.Notification.Timeout = 0;
//False表示Notification将被存于内存中，True表示存于数据库中，选择True可以保证即便数据库重启之后，消息仍然不会丢失
    cmd.Notification.IsPersistent = true;//
    OracleDataReader odr = cmd.ExecuteReader();//
    this.rtb1.AppendText("Registration completed. " + DateTime.Now.ToLongTimeString() + Environment.NewLine);
}private void btUnreg_Click(object sender, RoutedEventArgs e)
{//注销
    dep.RemoveRegistration(conn);this.rtb1.AppendText("Registration Removed. " + DateTime.Now.ToLongTimeString() + Environment.NewLine);
}private void OnNotificaton(object src, OracleNotificationEventArgs arg)
{//可以从arg.Details中获得通知的具体信息，比如变化数据的RowId
    DataTable dt = arg.Details;//......this.rtb1.Dispatcher.BeginInvoke(DispatcherPriority.Normal,new Action(() =>{this.rtb1.AppendText("Notification Received. " + DateTime.Now.ToLongTimeString()+"  Changed data(rowid): "+arg.Details.Rows[0]["rowid"].ToString() + Environment.NewLine);}));
}

Update tab_cn set val=1000 where id=1;
Commit;

if (dep == null || !dep.IsEnabled)
{OracleCommand cmd = new OracleCommand("select * from tab_cn", conn);dep = new OracleDependency(cmd);dep.QueryBasedNotification = false;dep.RowidInfo = OracleRowidInfo.Include;dep.OnChange += new OnChangeEventHandler(OnNotificaton);//
    cmd.Notification.IsNotifiedOnce = false;cmd.Notification.Timeout = 0;cmd.Notification.IsPersistent = true;//
    OracleDataReader odr = cmd.ExecuteReader();this.rtb1.AppendText("Registration completed. " + DateTime.Now.ToLongTimeString() + Environment.NewLine);
}