index.html

<!DOCTYPE html>
<html>
  <head>
      <title></title>
  </head>
  <body>

      <div id="app">
           <button type="button" name="button" id="btn" >点击按钮</button>
      </div>

      <script type="text/javascript">
          function mem(f,wait,mus){
            var timeout,
            startTime = new Date();
            return function(){
              var context=this,
              args=arguments;
              curTime = new Date()
              clearTimeout(timeout)
              if(curTime-startTime>=mus){
                f.call(context)
                startTime = curTime
              }else {
                timeout = setTimeout(f,wait)
              }
            }
          }
          function f(){
            console.log('ffff')
          }
          window.onload=function(){
            var btn = document.getElementById('btn')
            console.log('btn',btn)
            btn.onclick= mem(f,1000,3000)
          }
      </script>
  </body>
</html>