C#使用Channel实现异步任务之间的通信

channel中也是有一个ConcurrentQueue来维护的

using System.Threading.Channels;

var channel = Channel.CreateUnbounded<Message>();

//在赋值的时候，两个Task就开始执行了，下面的await就是为了等待执行完成
var sender1 = SendMessageAsync(channel.Writer, 1);
var sender2 = SendMessageAsync(channel.Writer, 2);
var receiver = ReceiveMessageAsync(channel.Reader, 3);

await Task.WhenAll(sender1, sender2);
channel.Writer.Complete();
await receiver;

async Task SendMessageAsync(ChannelWriter<Message> writer, int id)
{
    for (int i = 0; i <= 20; i++)
    {
        await writer.WriteAsync(new Message(id, i.ToString()));
        Console.WriteLine($"Thread {id} sent {i}");
        await Task.Delay(100);
    }
}

async Task ReceiveMessageAsync(ChannelReader<Message> reader, int id)
{
    // try
    // {
    //     while (!reader.Completion.IsCanceled)
    //     {
    //         var message = await reader.ReadAsync();
    //         Console.WriteLine($"Thread {id} received {message.Content} from {message.FromId}");
    //     }
    // }
    // catch (ChannelClosedException)
    // {
    //     Console.WriteLine($"Thread {id} channel closed");
    // }

    await foreach (var message in reader.ReadAllAsync())
    {
        Console.WriteLine($"Thread {id} received {message.Content} from {message.FromId}");
    }
}

record Message(int FromId, string Content);