text: /*
   * @Descripttion: 
   * @version: 
   * @Author: qianlishi
   * @Date: 2021-12-11 14:48:27
   * @LastEditors: qianlishi
   * @LastEditTime: 2021-12-13 10:16:48
   */
  /**
   * 函数节流
   */
  export function _throttle(fn,delay){
      let timer
      let delay = delay || 1000;   //一秒内触发一次
      return function(...args){
          const context = this
          let canExecute = !timer
          if(canExecute){
              fn.apply(context,args)
          }else{
              clearTimeout(timer)
          }
          timer = setTimeout(() => {
              timer = null
          }, delay);
      }
  } 