$.fn.scrollimg = function(options)
{
	
	//最多不超过20张
	
	var pre = $(this).find(".leftBar");
	var next = $(this).find(".rightBar");
	
	var imgslide = $(this).find(".slideli");
	var imgli = $(this).find("li");
	var imglilast = imgli.filter(":last-child");
	var imgl = imgslide.css("left");
	var imgnum = parseInt(imgl,10);
	
	var allimg =  imgli.index(imglilast);

      pre.click(function(){	  	   
	  if(imgnum < 0 ){
	  imgnum = (imgnum + 170)
	  imgl = imgnum+"px"	  
      imgslide.animate({left: imgl}, "slow");
	  }
	  });
	
	  next.click(function(){	  	   
	  if(imgnum > allimg*-170 ){	  
	  imgnum = (imgnum - 170)	  
	  imgl = imgnum+"px"	  	  
	  
	  imgslide.animate({left: imgl}, "slow");
      }	
	  
      });
	  
	  
	  
	   setInterval(scrollr,3000);  

  function scrollr()   
   {   
      
	  if(imgnum > allimg*-170 ){	  
	  imgnum = (imgnum - 170)	  
	  imgl = imgnum+"px"	  	  
	  
	  imgslide.animate({left: imgl}, "slow");
      }else{
	
	   imgnum=-170;
	  }	

   }   
      
	 


};