Question

In general I get C#’s lambda syntax. However the anonymous thread syntax isn’t completely clear to me. Can someone explain what a thread creation like this is actually doing? Please be as detailed as possible, I’d love to have a sort of step-by-step on the magic that makes this work.

(new Thread(() => {
        DoLongRunningWork();
        MessageBox.Show("Long Running Work Finished!");
    })).Start();

The part that I really don’t understand is the Thread(() => ...

When I use this syntax it seems like I remove a lot of the limits of a traditional ThreadStart such as having to invoke on a method that has no parameters.

Thanks for your help!

Answer 1

() => ... just means that the lambda expression takes no parameters. Your example is equivalent to the following:

void worker()
{
    DoLongRunningWork();
    MessageBox.Show("Long Running Work Finished!");
}

// ...

new Thread(worker).Start();

The { ... } in the lambda let you use multiple statements in the lambda body, where ordinarily you’d only be allowed an expression.

This:

() => 1 + 2

Is equivalent to:

() => { return (1 + 2); }