Wes' Puzzling Blog

I looked at the example in the Codeplex. I am wondering what would happen if I create another class that implements IMessageSender in the same Assembly.

for example,

all the code as in the example and then add this

[code]

public class regularMailer : ImessageSender

{

........

public void Send(....) //.... means if there are parameters that will be added

{

  System.Console.WriteLine("generate a PDF version and print");

}

}

[/code]

now I will have two classes that have the same footprint of IMessageSender.

Also, what if I want to create different assemblies and put them in the same folder? How will the MEF example work?

At the rate I am confused about MEF I will be flooding with lot of comments in this thread :)

I wrote a small app to do a task scheduler. It is a simple app that runs several tasks in their own thread. The code below is something I whiffed in my lunch time. The point I am trying to emphasis ( at least that is what I think ) is that something similar to MEF / plugin can be done without doing anything application specific(as defined by the author).

Here is my code:

------------------------------------------

static void Main(string[] args)

{

   Console.WriteLine("Starting FluEmails....at {0}", System.DateTime.Now.TimeOfDay);

   ArrayList taskStack = getTasks();

   foreach(object aTask in taskStack)

   {

      ITask thisTask = (ITask)aTask;

      ThreadStart task = new ThreadStart (thisTask.execute );

      Thread thread = new Thread (task);

      thread.Start ();

   }

   Console.WriteLine("Exiting FluEmails  ..... at {0}",System.DateTime.Now.TimeOfDay );

   Console.ReadLine ();

}

static ArrayList getTasks()

{

ArrayList allTasks = new ArrayList();

   Assembly assembly = Assembly.Load(Assembly.GetCallingAssembly().FullName );

   foreach (Type type in assembly.GetTypes())

   {

if (type.IsClass == true)

{

// create an instance of the object

try

{

object ClassObj = Activator.CreateInstance(type);

if (ClassObj is ITask )

{

allTasks.Add((ITask)ClassObj);

}

}

catch(MissingMethodException ex)

{

Console.WriteLine (ex.Message);

}

}        

   }

   return allTasks;

}

---------------------------------------------

ITask is an interface that has execute() method.

some task classes that I created are:

--------------------------------

public class EmailTask :ITask

{

public EmailTask()

{

}

public void execute()

{  

//get Data from database

//send emails

}

}

public class Announcer :ITask

{

public Announcer()

{

}

public void execute()

{

keepShoutingIDID();

}

}

----------------------------------------------

So how does MEF benefits over my approach?