C#

Date and Time Data

Date and time data consists of valid date or time combinations. For example, valid date and time data includes both "4/01/98 12:15:00:00:00 PM" and "1:28:29:15:01 AM 8/17/98". Date and time data is stored using the datetime and smalldatetime data types in Microsoft® SQL Server™ 2000. Use datetime to store dates in the range from January 1, 1753 through December 31, 9999 (requires 8 bytes of storage per value). Use smalldatetime to store dates in the range from January 1, 1900 through June 6, 2079 (requires 4 bytes of storage per value).

class Global
{
   public static int a = 20;
}

class C
{
   void Method1()
   {
      Global.a = 30;
      Console.WriteLine(Global.a); // prints 30
      Method2();
      Console.WriteLine(Global.a); // prints 100
   }

   void Method2()
   {
      Global.a = 100;
   }
}

public event EventHandler HandleThis;

void OnHandleThis(EventArgs e)
{
   if (HandleThis != null)
   {
      HandleThis(this, e);
   }
}

void OnHandleThis(EventArgs e)
{
   EventHandler handler = HandleThis;
 
   if (handler != null)
   {
      handler(this, e);
   }
}

Gizz quoted his supplier:

You should only ever add/remove an event handler once in most applications. It is not designed by Microsoft to have event handlers added and removed continuously as a method to controlling these things.

Gizz continued to quote his supplier:

This is because an event handler is usually dealt with in another thread (or how else could it be generated for the application)

and adding/removing notifications to the other thread can easily be the subject of racetrack timing errors.