防抖

export const antiShake= (fn, t) => {
    let delay = t || 500
    let timer
    return function () {
      let args = arguments;
      if (timer) {
        clearTimeout(timer)
      }
      let callNow = !timer
      timer = setTimeout(() => {
      timer = null
    }, delay)
       if (callNow) fn.apply(this, args)
    }
}