// 創(chuàng)建監(jiān)聽(tīng)器
var updateLayout = _.debounce(function(e) {

 // Does all the layout updating here

}, 500); // 最低500毫秒運(yùn)行一次

// Add the event listener
window.addEventListener("resize", updateLayout, false);
…這段Underscore.js代碼底層實(shí)際上是用interval檢查事件函數(shù)調(diào)用的頻度：

// 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.
_.debounce = function(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);
 };
};

// MooTools
Function.implement({
 debounce: function(wait, immediate) {
  var timeout,
      func = this;
  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);
  };
 }
});

// Use it!
window.addEvent("resize", myFn.debounce(500));