debounce javascript code example
Example 1: js throttle function
function throttle (callback, limit) {
var wait = false; // Initially, we're not waiting
return function () { // We return a throttled function
if (!wait) { // If we're not waiting
callback.call(); // Execute users function
wait = true; // Prevent future invocations
setTimeout(function () { // After a period of time
wait = false; // And allow future invocations
}, limit);
}
}
}
// Usage Example:
// On scroll, allow function to run at most 1 time per 100ms
window.addEventListener("scroll", throttle(function(){
/*stuff to be throttled*/
}, 100));
Example 2: js debounce
// Returns a function, that, as long as it continues to be invoked, will not
// be triggered. The function will be called after it stops being called for
// N milliseconds. If `immediate` is passed, trigger the function on the
// leading edge, instead of the trailing.
function debounce(func, wait, immediate) {
var timeout;
return function() {
var context = this, args = arguments;
var later = function() {
timeout = null;
if (!immediate) func.apply(context, args);
};
var callNow = immediate && !timeout;
clearTimeout(timeout);
timeout = setTimeout(later, wait);
if (callNow) func.apply(context, args);
};
};
// Usage:
var myEfficientFn = debounce(function() {
// All the taxing stuff you do
}, 250);
window.addEventListener('resize', myEfficientFn);
Example 3: javascript debounce function
// This is from David Walshes Blog Post
// https://davidwalsh.name/javascript-debounce-function
// A very simplified but effective version of Underscores debounce function
function debounce(func, wait, immediate) {
var timeout;
return function() {
var context = this, args = arguments;
var later = function() {
timeout = null;
if (!immediate) func.apply(context, args);
};
var callNow = immediate && !timeout;
clearTimeout(timeout);
timeout = setTimeout(later, wait);
if (callNow) func.apply(context, args);
};
};
Example 4: throttoling javascript
function throttle (callback, limit) {
var wait = false; // initial step when we are nit waiting
return function () { // returnimg a throttled function
if (!wait) { // while not waiting
callback.call(); // Executing users function
wait = true; // Preventing future invocations
setTimeout(function () { // after certain interval of time
wait = false; // allow future invocations
}, limit);
}
}
}
// Usage Example:
// On scroll, allow function to run at most 1 time per 100ms
window.addEventListener("scroll", throttle(function(){
/*stuff to be throttled*/
}, 100));