Question about the return of profitability

Question

Example:

 public static IEnumerable<BigInt> EvenNumbers(IEnumerable<BigInt> numbers)  
 {  
     foreach (BigInt number in numbers)  
     {  
         if (number % 2 == 0)  
         {  
             yield return number;  
         }  
     }  
 }  

This will only return values ​​matching the criteria (n% 2 == 0). But what is the difference between the returned number of returns; and return number ;?

If I say that it returns a return number, will it return every number of the calling function and so on? Where can I find some details about what is going on behind the scenes?

thanks

Answer 1

"return" ( BigInt, IEnumerable<BigInt>. Jon Skeet ( ) 6 # ( - ; -p).

---

edit - , , ; , , . , , yield return !

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
static class Program
{
    static void Main()
    {
        IEnumerable<int> source = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
        foreach (int value in EvenNumbers(source))
        {
            Console.WriteLine(value);
        }
    }

    public static IEnumerable<int> EvenNumbers(IEnumerable<int> numbers)
    {
        return new EvenEnumerable(numbers);
    }
    class EvenEnumerable : IEnumerable<int>
    {
        private readonly IEnumerable<int> numbers;
        public EvenEnumerable(IEnumerable<int> numbers) {
            this.numbers = numbers;
        }
        public IEnumerator<int> GetEnumerator()
        {
            return new EvenEnumerator(numbers);
        }
        IEnumerator IEnumerable.GetEnumerator() { return GetEnumerator(); }
    }
    class EvenEnumerator : IEnumerator<int>
    {
        private readonly IEnumerable<int> numbers;
        public EvenEnumerator(IEnumerable<int> numbers)
        {
            this.numbers = numbers;
        }
        private int current;
        void IEnumerator.Reset() { throw new NotSupportedException(); }
        public int Current { get { return current; } }
        object IEnumerator.Current { get { return Current; } }
        IEnumerator<int> iter;
        public bool MoveNext()
        {
            if (iter == null) iter = numbers.GetEnumerator();
            while (iter.MoveNext())
            {
                int tmp = iter.Current;
                if (tmp % 2 == 0)
                {
                    current = tmp;
                    return true;
                }
            }
            return false;
        }
        public void Dispose()
        {
            if (iter != null)
            {
                iter.Dispose();
                iter = null;
            }
        }
    }
}

Answer 2

yield return IEnumerator, . for MoveNext, .

IL-