NotificationTextWriter

 using  System;
 using  System.Diagnostics;
 using  System.IO;
 using  System.Text;

 namespace  BA.Core.IO {
     /// <summary>
     /// Used for handling notification on a TextWriter
     /// </summary>
     public  class  NotificationTextWriter :TextWriter  {
         public  event  TextNotificationHandler  TextNotification;

         public  NotificationTextWriter() { }
         public  NotificationTextWriter(TextNotificationHandler  notificationFunc) {
             TextNotification += notificationFunc;
         }

         protected  void  OnTextNotification(TextNotificationArgs  args) {
             if (TextNotification != null )
                 TextNotification(this ,args);
         }
         public  override  void  Write(char [] buffer,int  index,int  count) {
             this .Write(new  String (buffer,index,count));
         }
         public  override  void  Write(string  value) {
             OnTextNotification(new  TextNotificationArgs () { Output = value });
         }
         public  override  Encoding  Encoding {
             get  { return  Encoding .Default; }
         }
     }
     public  delegate  void  TextNotificationHandler (object  sender,TextNotificationArgs  e);

     public  class  TextNotificationArgs :EventArgs  {
         public  string  Output { get ; set ; }
     }
 }