SqlDependencyEx - TableListener Example

CreateTables.sql

/****** Object:  Table [dbo].[Table1]    Script Date: 6/22/2017 10:42:23 PM ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[Table1](
	[Id] [int] IDENTITY(1,1) NOT NULL,
	[Description] [nchar](10) NULL,
 CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED 
(
	[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

/****** Object:  Table [dbo].[Table2]    Script Date: 6/22/2017 10:42:23 PM ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[Table2](
	[Id] [int] IDENTITY(1,1) NOT NULL,
	[Description] [nchar](10) NULL,
 CONSTRAINT [PK_Table2] PRIMARY KEY CLUSTERED 
(
	[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

insert into table1 ([description]) values ('abc')
insert into table2 ([description]) values ('def')

Program.cs

  public class Program
  {
    private const string Connection = "Data Source=(local);Initial Catalog=master;Integrated Security=True";
    private const string Database = "TestDatabase";

    private static void Main(string[] args)
    {
      var listener = TableUpdateListener("Table1", 1, FirstTableUpdated);
      var listener2 = TableUpdateListener("Table2", 2, SecondTableUpdated);
      listener.Start();
      listener2.Start();
      Console.WriteLine("______________Escuchando_______________");
      Console.ReadKey();
      listener.Stop();
      listener2.Stop();
    }

    private static SqlDependencyEx TableUpdateListener(string tableName, int identity, EventHandler<TableChangedEventArgs> handler)
    {
      var listener = new SqlDependencyEx(
        Connection,
        Database,
        tableName,
        listenerType: NotificationTypes.Update,
        identity: identity);
      listener.TableChanged += handler;
      return listener;
    }

    private static void SecondTableUpdated(object o, SqlDependencyEx.TableChangedEventArgs e)
    {
      Console.WriteLine($"SecondTableUpdated {e.Data}");
    }

    private static void FirstTableUpdated(object o, SqlDependencyEx.TableChangedEventArgs e)
    {
      Console.WriteLine($"FirstTableUpdated {e.Data}");
    }
  }

I would agree that sharing events from the say a console application or a windows service through other events will make your application

• Easier to understand
• Debug
• Composable
• Testable

I wouldn't recommend WCF as it is so complicated every time I try to debug it. WebSockets yes and Server Sent Events in ServiceStack as an example are in my experience easier to understand and readily cross platform.