$(function(){		//返回顶部		$('.btop').hover(function(){			$(this).find('img').attr('src','${base!}/${img_path!}/backtop2.gif');		},function(){			$(this).find('img').attr('src','${base!}/${img_path!}/backtop1.gif');		});		window.onscroll = function(){			var scrT = document.documentElement.scrollTop || document.body.scrollTop;			if(scrT > 0){				$('.btop').show();			}else {				$('.btop').hide();			};		};		$('.btop').click(function(){			document.documentElement.scrollTop = document.body.scrollTop = 0;			$('.btop').hide();		});	})