1-ienumerable-with-yield

CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
	public static void Main()
	{
		//obtain a list of pets
		IEnumerable<Pet> pets = CreateListOfPets();	
		
		//pass the pets list into our GetDogs method and yield return the first 2 dogs we find.
		foreach (var dog in  GetDogsUsingYield(pets).Take(2))
		{
			Console.WriteLine("- retrieved: " + dog.Name + " the " + dog.Animal);
		}
	}
	

	public static IEnumerable<Pet> GetDogsUsingYield(IEnumerable<Pet> pets){
		foreach (var pet in pets)
		{
			Console.WriteLine("Processing with yield: " + pet.Animal);
			if(pet.Animal=="Dog")
			{
				Console.WriteLine("yielding: " + pet.Animal);
				yield return pet;
			}
		}
	}
	
public static IEnumerable<Pet> CreateListOfPets(){
	return new List<Pet>{
		new Pet{Animal="Dog",Colour="Black", Name="Rocky"},
		new Pet{Animal="Cat",Colour="Black", Name="Betty"},
		new Pet{Animal="Dog",Colour="White", Name="Fluffy"},
		new Pet{Animal="Elephant",Colour="Grey", Name="Nellie"},
		new Pet{Animal="Dog",Colour="Brown", Name="Lassie"},
		new Pet{Animal="Cat",Colour="Brown", Name="Mr Jinx"},
		new Pet{Animal="Mouse",Colour="Brown", Name="Micky"},
		new Pet{Animal="Cat",Colour="Black", Name="Tom"},
		new Pet{Animal="Turtle",Colour="Green", Name="Leonardo"},
		new Pet{Animal="Yoda",Colour="Brown", Name="Lizard"}
	};
	}	
}


public class Pet{
	public string Animal {get;set;}
	public string Colour {get;set;}
	public string Name {get;set;}
}