Strategy design pattern example

gistfile1.cs

namespace DesignPatterns
{
	public class User
	{
		public string Name { get; set; }
		public int Age { get; set; }
		public override string ToString()
		{
			return string.Format("{0} {1}", Name, Age);
		}
	}
	
	/// <summary>
	/// Compares two users based on name.
	/// </summary>
	public class NameSorter : IComparer<User>
	{
		public int Compare(User x, User y)
		{
			return x.Name.CompareTo(y.Name);
		}
	}
	
	/// <summary>
	/// Compares two Users based on their age.
	/// </summary>
	public class AgeSorter : IComparer<User>
	{
		public int Compare(User x, User y)
		{
			return x.Age.CompareTo(y.Age);
		}
	}
	
	/// <summary>
	/// A simple extension method class for pretty-printing the
	/// List<Users> collection.
	/// </summary>
	public static class ListExtension
	{
		public static string Print(this List<User> list)
		{
			StringBuilder builder = new StringBuilder();
			foreach (User user in list)
			{
				builder.AppendLine(user.ToString());
			}
			
			return builder.ToString();
		}
	}
}