What is ApplicationException class used for?-interview04032012

If you are creating a large application or creating components that are used by other applications, you might want to define your own exception classes based on the ApplicationException class. For example, the following code defines a class for the UserLoggedOnException: public class UserLoggedOnException : System.ApplicationException { // Exception constructor (overloaded). public UserLoggedOnException() : this("The user is already logged on to the server", null) { } public UserLoggedOnException(string message) : this(message, null) { } public UserLoggedOnException(string message, Exception inner) : base(message, inner) { } } The preceding UserLoggedOnException class inherits its properties and methods from the ApplicationException base class. The new exception class provides only its own constructor to set the default message to display. This is a standard practice.