Tuples in C# 4.0

Tuples in C#

One of my favorite features in .NET 4 is the addition of the Tuple.  Tuples allow you to easily capture related values without having to go through the trouble of creating a new class.  It's a much more flexible concept than the KeyValuePair class because they can hold up to 8 values. 

Tuple is a borrowed concept from F# that's been wedged into C# using the power of generics (and the copying and pasting of a class about 8 times). 

Here's an example of the usage

   1: public void Tuple()

   2:          {

   3:              var tup = new System.Tuple<int, string, DateTime>(1, "Brian", DateTime.Now);

   4:              Debug.Write(tup.Item1 + tup.Item2 + tup.Item3);

   5:          }

Here's the class I used above (The version that holds 3 generic values)

   1:  namespace System

   2:  {

   3:      [Serializable]

   4:      public class Tuple<T1, T2, T3> : IStructuralEquatable, IStructuralComparable, IComparable, ITuple

   5:      {

   6:          public Tuple(T1 item1, T2 item2, T3 item3);

   7:   

   8:          public T1 Item1 { get; }

   9:       

  10:          public T2 Item2 { get; }

  11:       

  12:          public T3 Item3 { get; }

  13:   

  14:          public override bool Equals(object obj);

  15:          

  16:          public override int GetHashCode();

  17:        

  18:          public override string ToString();

  19:      }

  20:  }

Interesting to note that, yes there are 8 different versions of the class to support Tuples that hold up to 8 values.

For more details check - http://msdn.microsoft.com/en-us/library/system.tuple.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-1