[CheckId] CA1009 [Warning] CA1009: Declare event handlers correctly [Description] 
Event handler methods take two parameters. The first is of type System.Object and is named "sender". This is the object that raised the event. The second parameter is of type System.EventArgs and is named "e". This is the data that is associated with the event. Event handler methods should not return a value; in the C# programming language, this is indicated by the return type void.