1.ģӻ༭ģʽ
2.ԶHTMLҼ
3.Դģʽ´뼴ɡ

<!--صHTML-->
<div id='gotop' class='success textcenter clearfix' style='width:50px;position:absolute;right:0;bottom:0;margin:0;display:none;cursor:pointer;line-height:20px;height:20px;'>
   
</div>
<script>
   window.addEvent('domready',function(){
       $('gotop').inject(document.body).addEvent('click',function(){
		   new Fx.Scroll(window,{link:'cancel'}).toTop();
	   }).setOpacity(.8);
	   
	   this.addEvent('scroll',function(){
	        if(window.getScrollTop()>100){
		    $('gotop').setStyle('top',window.getSize().y + window.getScrollTop() - $('gotop').getSize().y).show();	
	       }else{
		      $('gotop').hide();
		   }
	   });
   
   });
</script>