What is throttling in JavaScript and how does it work?

What is throttling in JavaScript and how does it work?

Throttling in JavaScript is a technique used to limit the number of times a function is executed over time. It ensures that a function is only called at most once in a specified time interval, which can improve performance, especially in scenarios like scrolling or resizing.

Can you give me an example of how to implement throttling?

Sure! Here's a simple example using a throttle function:

function throttle(func, limit) {
    let lastFunc;
    let lastRan;
    return function() {
        const context = this;
        const args = arguments;
        if (!lastRan) {
            func.apply(context, args);
            lastRan = Date.now();
        } else {
            clearTimeout(lastFunc);
            lastFunc = setTimeout(function() {
                if ((Date.now() - lastRan) >= limit) {
                    func.apply(context, args);
                    lastRan = Date.now();
                }
            }, limit - (Date.now() - lastRan));
        }
    };
}

This function will ensure that func is called at most once every limit milliseconds.

What are some use cases for throttling?

Throttling is commonly used in scenarios like handling scroll events, resizing windows, or making API calls at a controlled rate to avoid overwhelming the server.

How does throttling differ from debouncing?

Throttling ensures a function is called at regular intervals, while debouncing delays the function call until after a specified time has passed since the last call. Throttling is useful for continuous events, while debouncing is better for events that occur in bursts.