Generic Class

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http://www.tutorialspoint.com/csharp/csharp_generics.htm

A generic class is one which has different versions (or 'specializations') depending on the type parameters which are passed to it in angle brackets when an instance is created or a static member is accessed.

For example System.Collections.Generic.Dictionary is a generic class in the .NET framework which takes two type parameters representing the types of the keys and values. This line:

var dict = new Dictionary();

creates an instance of this class where the keys are strings and the values are ints.

In effect, K is replaced by string and V is replaced by int, wherever these parameters appear in the definition of the generic class and its members.

It is possible for type parameters to be subject to 'constraints'. For example, if a generic class is defined as follows:

class MyClass where T : IEnumerable, class, new()
{.....}


then T must be replaced with a type which implements IEnumerable, is a reference type and has a constructor which takes no parameters.