void Something() => System.Console.WriteLine("Something is done");
Task t = new Task(delegate {Something();});
t.Start();  // nothing activates unless the below code is uncommented
// System.Console.WriteLine(33);  //displays "33 \nSomething is done" as long as not commented out

I don't understand something fundamental about Task. In the code above, if line 4 is commented out, nothing is written on the console, but if you write in System.Console.WriteLine(33), then the number 33 displays AND "Something is done" displays.

1. I don't understand why t.Start() doesn't write "Something is done".
2. Why does writing anything after t.Start(), activate it?

Thank you.

Update: This is my whole program. It is intended to understand the behavior of Task, so the program is small.

CodePudding user response：

The main thread does not block and hence is exiting immediately without Console.WriteLine. Console.WriteLine is done on the main thread.

Since this is a console app, the call to the Wait method is necessary to prevent the app from terminating before the task finishes execution.

t.Start();
t.Wait();  

Reference: https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task.start?view=net-7.0#system-threading-tasks-task-start

Another way is to make the Main method async.

public static async Task Main()
{
    Task t = new Task(delegate { Something(); });
    t.Start();
    await t;
}