Generics in C#, Free online C# Programming Tutorial...

Both Java and C++ have the feature of Generics. In C# it is no different. Generics is essentially the ability to have type parameters on our own defined types. They are also called parameterized types. .NET’s System.Collections.Generic namespace has a number of useful generic classes available for our use.

The following example illustrates the use of generics in C#:

 public class GenericContainer <T>
{ 
   private T element; 
   public GenericContainer(T element) 
   { 
      this.element =element; 
   } 
   public T getElement() 
   { 
      return this.element;  
   }
}

The instantiation of objects from the above GenericContainer class is pretty simple:

GenericContainer<int> a = new GenericContainer<int>(34);
// Generic Container of int type

GenericContainer<string> a = new GenericContainer<string>(“Hello World”);
// Generic Container of string type

GenericContainer<double> a = new GenericContainer<double>(3.04);
// Generic Container of double type

From the above GenericContainer class you could instantiate any number of containers, each having the capability to store a different type of element. While the example is far from practical, it does illustrate the basic idea of generics.

Note that you can have any number of type parameters in a generic class as per your needs. Each additional type parameter has to have a different name. We used T in the above example and if we needed to have an additional type parameter we could have named it as S, for example.

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