<script>
    $(".banpic li:first").clone(true).appendTo(".banpic")
        $(".banpic li:last").prev("li").clone(true).prependTo(".banpic")

            $(function () {
                var container = $('.banner');
                var list = $('.banpic');
                var prev = $('.prev');
                var next = $('.next');
                var len = $(".banpic li").length-2;
                var index = 1;
                var interval = 5000;
                var timer;
                list.width(1000*(len+2));
                function animate (offset) {
                    var left = parseInt(list.css('left')) + offset;

                    if (offset>0) {
                        offset = '+=' + offset;
                    }
                    else {
                        offset = '-=' + Math.abs(offset);
                    }
                    list.animate({'left': offset}, 1000, function () {
                        if(left > -200){
                            list.css('left', -1000 * len);
                        }
                        if(left < (-1000 * len)) {
                            list.css('left', -1000);
                        }
                    });
                }
                function play() {
                    timer = setTimeout(function () {
                        next.trigger('click');
                        play();
                    }, interval);
                }
                
                function stop() {
                    clearTimeout(timer);
                }

                next.bind('click', function () {
                    if (list.is(':animated')) {
                        return;
                    }
                    if (index == len) {
                          index = 1;
          
                     }
                     else {
                     index += 1;
           
                    }
                    animate(-1000);
                });

                prev.bind('click', function () {
                    if (list.is(':animated')) {
                        return;
                    }
                     if (index == 1) {
                     index = len;
           
                        }
                    else {
                     index -= 1;
        
                        }
                    animate(1000);
                });
                 container.hover(stop, play);
            play();
            });

</script>

题主把一个简单的幻灯片弄得太复杂了

    var $ImgsLeft=$('.no-select .left .arrow-img')
  var n=$('li img').size();
            $ImgsLeft.click(function(){
                if(n>=0)
        {
            $('ul').stop(true,true).animate({left:'-=46px'});
            n--
        }
})