C# Pause the loop and continue after button is clicked

Question

I have a method that is called after the initialization component, the method signature is like:

public async void method_name ()
{
    // code ...
}

Inside that method, I have a loop running with 4 different if statements. I need the loop to pause at each if statements and wait for the user to press a button. Since pressing that button will add info and stuff. Once the button is pressed, I want the loop to continue and of course pause at the next if statements.

I thought about doing it like await Task.Delay(30000); but if the user is done entering the info before that timer is over, he/she will just be waiting. and That's not efficient.

Answer 1

You can do that with TaskCompletionSource . Create it and await its Task property and when a button is clicked use it to complete that task. That allows to asynchronously wait for the user input without blocking a thread or using Task.Delay .

TaskCompletionSource<bool> _tcs;

async Task Foo()
{
    // stuff
    _tcs = new TaskCompletionSource<bool>();
    await _tcs.Task
    // other stuff
}

void ButtonClicked(object sender, EventArgs e)
{
    _tcs.SetResult(false);
}