C#基础之Async和Await 的异步编程

官方文档地址：https://docs.microsoft.com/zh-cn/dotnet/csharp/programming-guide/concepts/async/

Coffee cup = PourCoffee();
Console.WriteLine("coffee is ready");
Task<Egg> eggTask = FryEggs();
Task<Bacon> baconTask = FryBacon();
Task<Toast> toastTask = ToastBread();
Toast toast = await toastTask;
ApplyButter(toast);
ApplyJam(toast);
Console.WriteLine("toast is ready");
Juice oj = PourOJ();
Console.WriteLine("oj is ready");

Egg eggs = await eggTask;
Console.WriteLine("eggs are ready");
Bacon bacon = await baconTask;
Console.WriteLine("bacon is ready");

Console.WriteLine("Breakfast is ready!");

static async Task Main(string[] args)
{
    Coffee cup = PourCoffee();
    Console.WriteLine("coffee is ready");
    var eggsTask = FryEggsAsync();
    var baconTask = FryBaconAsync();
    var toastTask = MakeToastWithButterAndJamAsync();

    var eggs = await eggsTask;
    Console.WriteLine("eggs are ready");
    var bacon = await baconTask;
    Console.WriteLine("bacon is ready");
    var toast = await toastTask;
    Console.WriteLine("toast is ready");
    Juice oj = PourOJ();
    Console.WriteLine("oj is ready");

    Console.WriteLine("Breakfast is ready!");

    async Task<Toast> MakeToastWithButterAndJamAsync(int number)
    {
        var toast = await ToastBreadAsync(number);
        ApplyButter(toast);
        ApplyJam(toast);
        return toast;
    }
}

static async Task Main(string[] args)
{
    Coffee cup = PourCoffee();
    Console.WriteLine("coffee is ready");
    var eggsTask = FryEggsAsync();
    var baconTask = FryBaconAsync();
    var toastTask = MakeToastWithButterAndJamAsync();

    var allTasks = new List<Task>{eggsTask, baconTask, toastTask};
    while (allTasks.Any())
    {
        Task finished = await Task.WhenAny(allTasks);
        if (finished == eggsTask)
        {
            Console.WriteLine("eggs are ready");
        }
        else if (finished == baconTask)
        {
            Console.WriteLine("bacon is ready");
        }
        else if (finished == toastTask)
        {
            Console.WriteLine("toast is ready");
        }
        allTasks.Remove(finished);
    }
    Juice oj = PourOJ();
    Console.WriteLine("oj is ready");
    Console.WriteLine("Breakfast is ready!");

    async Task<Toast> MakeToastWithButterAndJamAsync(int number)
    {
        var toast = await ToastBreadAsync(number);
        ApplyButter(toast);
        ApplyJam(toast);
        return toast;
    }
}