C#多线程の多个线程处理一个任务，然后执行其余

Posted 2020-10-06

In the comments, I was told that I should avoid Thread.Sleep(), all right, let‘s try this:
1. you could wrap the parallel.foreach within a task and manually add your completedCallback()

public Task DoWorkAsync(DoWorkCompletedCallback completedCallback)
{
    return Task.Factory.StartNew(
    { 
        Parallel.Foreach

        //call callback manually
        completedCallback();
    });
}

 

2. Use ContinueWith

Task.Factory.StartNew(
    { 
        //do work
    }
    ).ContinueWith(completedCallback);

 

3. you could assign callback in the caller, it‘s the same as 2.

Task newTask = Task.Factory.StartNew(    
{ 
        //do work
});
newTask.ContinueWith(onCompleted);

 

4. consumer-publisher patterns
Producer Consumer problem

Assume you have a huge object hosting messages ConcurrentList<string>, task pushes a message ‘OnCompleted‘ to the object, on the other side, a listener subscribes the message, once a OnCompleted received, it will execute the continuation.