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Object-oriented Programming in C#
Reference types, Value types, and Patterns
The Singleton pattern

Problem: For some classes we wish to guarantee that at most one instance of the class can be made.

Solution: The singleton design pattern

/user/normark/oop-csharp-1/sources/c-sharp/patterns/singleton/template/singleton.csA template of a singleton class.

/user/normark/oop-csharp-1/sources/c-sharp/patterns/singleton/die/singleton-die.csA singleton Die class.

/user/normark/oop-csharp-1/sources/c-sharp/patterns/singleton/die/dieApp.csApplication of the singleton Die class.

/user/normark/oop-csharp-1/sources/c-sharp/patterns/singleton/die/outputOutput of singleton Die application.

A singleton Die is - most probably - not very useful.

On the next slide we will show a singleton Random, which solves a real problem