/// <summary>
/// 命令式生成质数
/// </summary>
/// <param name="amount"></param>
public static void GeneratePrimeByImperative(int amount)
{
foreach (var prime in PrimeGenerator.Generate(amount))
{
Console.WriteLine($"{prime}@{DateTime.Now}");
}
}
/// <summary>
/// 在执行链路中运行异步方法
/// 比如想在 Where() 中运行异步判断，但是 Where 不支持返回值 Task<bool>，所以可以使用 SelectMany 的重载方法来进行投影，并生成新的带原始数据的对象
/// </summary>
/// <returns></returns>
public static IObservable <int> RunAsyncCodeInPipeline()
{
return(Observable.Range(2, 9)
.SelectMany(x => PrimeGenerator.CheckPrimeAsync(x), (number, isPrime) => new { number, isPrime })
.Where(x => x.isPrime)
.Select(x => x.number));
}
/// <summary>
/// 在链路中中运行异步方法，而且结果顺序输出
/// 使用 Select 和 Concat 代替 SelectMany 就可以顺序输出
/// </summary>
/// <returns></returns>
public static IObservable <int> RunAsyncCodeInPipelineWithOrder()
{
return(Observable.Range(2, 9)
.Select(async x => new { number = x, isPrime = await PrimeGenerator.CheckPrimeAsync(x) })
.Concat()
.Where(x => x.isPrime)
.Select(x => x.number));
}
/// <summary>
/// Task 生成 Observable，使用 ToObservable。
/// 这个写法很简单，而且执行时间是耗时最长的 Task 时间，跟 AsyncAwaitGenerate 不一样
/// </summary>
/// <param name="amout"></param>
/// <returns></returns>
public static IObservable <int> TaskToObservable(int amout)
{
var o1 = PrimeGenerator.GenerateAsync(5).ToObservable();
var o2 = PrimeGenerator.GenerateAsync(5).ToObservable();
return(o1.Concat(o2) // 先用 Concat 连接两个集合
.SelectMany(primes => primes)); // 再用 SelectMany 投影每个值
}
/// <summary>
/// RunAsyncCodeInPipeline 的 linq 实现，更直观
/// </summary>
/// <returns></returns>
public static IObservable <int> RunAsyncCodeInPipelineByLinq()
{
var resule = from number in Observable.Range(2, 9)
from isPrime in PrimeGenerator.CheckPrimeAsync(number)
where isPrime
select number;
return(resule);
}
/// <summary>
/// 同步方法生成Observable，阻塞线程
/// </summary>
/// <param name="amount"></param>
/// <returns></returns>
public static IObservable <int> GeneratePrime(int amount)
{
return(Observable.Create <int>(o =>
{
foreach (var prime in PrimeGenerator.Generate(amount))
{
o.OnNext(prime);
}
o.OnCompleted();
return Disposable.Empty;
}));
}
/// <summary>
/// 简化版的异步方法生成Observable，不阻塞线程，可取消
/// </summary>
/// <param name="amount"></param>
/// <returns></returns>
public static IObservable <int> SimpleGeneratePrimeFromTask(int amount)
{
return(Observable.Create <int>((o, ct) =>
{
return Task.Run(() =>
{
foreach (var prime in PrimeGenerator.Generate(amount))
{
ct.ThrowIfCancellationRequested();
o.OnNext(prime);
}
o.OnCompleted();
}, ct);
}));
}
/// <summary>
/// AsyncAwait 模式生成Observable
/// 执行时间等于所有task总和
/// </summary>
/// <param name="amout"></param>
/// <returns></returns>
public static IObservable <int> AsyncAwaitGenerate(int amout)
{
return(Observable.Create <int>(async o =>
{
var primes1 = await PrimeGenerator.GenerateAsync(5);
foreach (var prime in primes1)
{
o.OnNext(prime);
}
var primes2 = await PrimeGenerator.GenerateAsync(5);
foreach (var prime in primes2)
{
o.OnNext(prime);
}
o.OnCompleted();
}));
}
/// <summary>
/// 异步方法生成Observable，不阻塞线程，可取消
/// </summary>
/// <param name="amount"></param>
/// <returns></returns>
public static IObservable <int> GeneratePrimeFromTask(int amount)
{
return(Observable.Create <int>(o =>
{
var cts = new CancellationTokenSource();
Task.Run(() =>
{
foreach (var prime in PrimeGenerator.Generate(amount))
{
cts.Token.ThrowIfCancellationRequested();
o.OnNext(prime);
}
o.OnCompleted();
}, cts.Token);
return new CancellationDisposable(cts);
}));
}
/// <summary>
/// 周期性地生成 Observable，均匀时间间隔
/// </summary>
/// <returns></returns>
public static IObservable <int> CreateByInterval()
{
return(Observable.Interval(TimeSpan.FromSeconds(2))
.SelectMany(_ => PrimeGenerator.GenerateAsync(3))
.SelectMany(primes => primes));
}
