我在这篇文章中读到：“ Rx 的乐趣：基于事件的异步模式 vs IObservable ”，不鼓励使用 EBAP。使用新的 Rx 扩展（类似于 msdn 的 PrimeNumberCalculator 示例）设计异步组件的最佳方式是什么？
先感谢您。
更新 我设法编写了自己的素数计算器，我想听听你的意见：
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
namespace ConsoleApplication13
{
public class PrimeNumberCalculator
{
private readonly Subject<int> primeSubject;
private IDisposable currentSubscription;
public PrimeNumberCalculator()
{
primeSubject = new Subject<int>();
Primes = primeSubject.Hide();
}
public IObservable<int> Primes{ get; private set; }
/// <summary>
/// Determine if n is prime.
/// </summary>
private static bool IsPrime(ArrayList primes, int n, out int firstDivisor)
{
bool foundDivisor = false;
bool exceedsSquareRoot = false;
int i = 0;
firstDivisor = 1;
// Stop the search if:
// there are no more primes in the list,
// there is a divisor of n in the list, or
// there is a prime that is larger than
// the square root of n.
while ( (i < primes.Count) && !foundDivisor && !exceedsSquareRoot)
{
// The divisor variable will be the smallest
// prime number not yet tried.
int divisor = (int)primes[i++];
// Determine whether the divisor is greater
// than the square root of n.
if (divisor * divisor > n)
{
exceedsSquareRoot = true;
}
// Determine whether the divisor is a factor of n.
else if (n % divisor == 0)
{
firstDivisor = divisor;
foundDivisor = true;
}
}
return !foundDivisor;
}
/// <summary>
/// Itereates from 1 to numberToTest and returns all primes.
/// </summary>
private IEnumerable<int> PrimeNumberIterator(int numberToTest)
{
var primes = new ArrayList();
var n = 5;
// Add the first prime numbers.
primes.Add(2);
primes.Add(3);
// Do the work.
while (n < numberToTest)
{
int firstDivisor;
if (IsPrime(primes, n, out firstDivisor))
{
// Report to the client that a prime was found.
yield return n;
Thread.Sleep(5000); //simulate long running task.
primes.Add(n);
}
// Skip even numbers.
n += 2;
}
}
/// <summary>
/// Begin a prime number exploration.
/// If there is some exploration in progress unsubscribe.
/// </summary>
public void IsPrime(int numberToTest)
{
if (currentSubscription != null) currentSubscription.Dispose();
currentSubscription = PrimeNumberIterator(numberToTest)
.ToObservable()
.Subscribe(primeSubject.OnNext);
}
/// <summary>
/// Cancel a prime number exploration
/// </summary>
public void Cancel()
{
if (currentSubscription != null) currentSubscription.Dispose();
}
}
internal class Program
{
private static void Main(string[] args)
{
var primeNumberCalculator = new PrimeNumberCalculator();
primeNumberCalculator.Primes.Subscribe(p => Console.WriteLine("Is prime {0}", p));
var exit = false;
do
{
Console.WriteLine("Write a number to explore and press enter: ");
var input = Console.ReadLine();
int primeToExplore;
if(int.TryParse(input, out primeToExplore))
{
primeNumberCalculator.IsPrime(primeToExplore);
}
else {
primeNumberCalculator.Cancel();
exit = true;
}
} while (!exit);
}
}
}