js 函数节流

//es6语法

export function debounce(func, delay) {
  let timer
  //返回一个函数，并拿到参数
  return function (...args) {
    if (timer) {
      cleartimeout(timer)
    }
    timer = settimeout(() => {
      func.apply(this, args)
    }, delay)
  }
}

//简单实现

var debounce = function(idle, action){
  var last
  return function(){
    var ctx = this, args = arguments
    cleartimeout(last)
    last = settimeout(function(){
        action.apply(ctx, args)
    }, idle)
  }
}