How Create a Scheduler (e.g. to schedule tweets, or an api request)

Question

I have a table of schedule items, they may be scheduled for the same time. I\'m wondering how to have them all execute at the correct time when:

The problem I see is

Answer 1

You can put the tasks in threads when you get want them to run:

public abstract class MyTask {
    public abstract void DoWork();
}


// ...

public void SomeTaskStarter()
{
    MyTask task = SomeFactoryMethodToCreateATaskInstance();

    new Thread(new ThreadStart(task.DoWork)).Start();
}

MyTask is an abstract class that represents a task to do and it defines a method, DoWork() that will do what you want. SomeFactoryMethodToCreateATaskInstance() will construct a concrete instance of a task and all you need to do is write DoWork() to do what you need to do:

public class Twitterer : MyTask
{
    private string _tweet;
    public Twitterer(string tweet)
    {
        _tweet = tweet;
    }
    public override DoWork()
    {
        TwitterApi api = new TwitterApi(); // whatever
        api.PostTweet(tweet);
    }
}

You will most assuredly want some kind of action of task completion. Whatever you do, the task completion routine should be threadsafe, and should probably be called via BeginInvoke()/EndInvoke() if you need to do any UI-ish work.

SomeTaskStarter() is best called from a windows service, and will most likely contain an argument with information about what task should be started, etc.