在utils/index.js 文件中

// 防抖 立即执行
function debounce(fn, arg) {
  // delay = delay || 1000;
  let delay = 1000;
  let timeout;
  return function() {
    let context = this;
    if (timeout) clearTimeout(timeout);

    let callNow = !timeout;
    timeout = setTimeout(() => {
      timeout = null;
    }, delay);
    if (callNow) fn.apply(context, arg);
  };
}

export { debounce };

src/directive/index.js 自定义指令：

import Vue from 'vue';

  import { debounce } from '@/utils';

Vue.directive('debounce', {
  bind(el, binding) {
    const [fn, ...args] = binding.value;
    el.addEventListener('click', debounce(fn, args));
  },
  unbind(el, binding) {
    const [fn, ...args] = binding.value;
    el.removeEventListener('click', debounce(fn, args));
  }
});

使用：

<el-button v-debounce="[handleDownload]">下载模版</el-button>      // 要执行的函数     handleDownload() {      console.log（）     },