Debouncer and Throttler

Debouncing and throttling are two rate-limiting strategies for handling rapid invocations. They solve different problems:

Debouncing waits for a pause in activity before executing. Use it when you want the last action in a burst (e.g., search-as-you-type).
Throttling executes immediately and then ignores subsequent calls until an interval elapses. Use it when you want the first action in a burst (e.g., preventing double-clicks).

Debouncer

The Debouncer delays execution until a specified period of inactivity has elapsed. Each new call resets the timer.

using MADE.Threading;

private readonly Debouncer debouncer = new() { Delay = TimeSpan.FromMilliseconds(300) };

public void OnSearchTextChanged(string text)
{
    debouncer.Debounce(() => PerformSearch(text));
}

In this example, if the user types "hello" character by character, the search only executes once - 300ms after the last keystroke.

Async debouncing

For async actions, use DebounceAsync:

public void OnSearchTextChanged(string text)
{
    debouncer.DebounceAsync(async () => await SearchApiAsync(text));
}

Cancelling a pending action

debouncer.Cancel();

Cleanup

Debouncer implements IDisposable. Dispose it when the owning component is torn down:

debouncer.Dispose();

Throttler

The Throttler limits execution to at most once per interval. The first call executes immediately; subsequent calls within the interval are suppressed.

using MADE.Threading;

private readonly Throttler throttler = new() { Interval = TimeSpan.FromMilliseconds(500) };

public void OnSubmitClicked()
{
    throttler.Throttle(() => SubmitForm());
}

If the user clicks the submit button three times in quick succession, only the first click triggers SubmitForm().

Async throttling

public void OnSubmitClicked()
{
    throttler.ThrottleAsync(async () => await SubmitFormAsync());
}

Choosing between Debouncer and Throttler

Scenario	Use
Search-as-you-type	Debouncer - wait for the user to stop typing.
Window resize handler	Debouncer - wait for the resize to finish.
Form submission button	Throttler - process the first click, ignore rapid follow-ups.
Scroll event handler	Throttler - execute at a steady rate during scrolling.
Auto-save on text change	Debouncer - save after the user pauses editing.

The key distinction: debouncing delays execution until after the burst ends, while throttling executes at the start of the burst and then rate-limits.

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