JS实现可用滑块滑动的缓动图代码

function $(id) { return document.getElementById(id); }
//缓动轮播图
var fhTimer;
var fhNum = 0;
var barNum = 0;
fhTimer = setInterval(marquee, 20);
function marquee() {
  fhNum--;
  barNum = fhNum;
  if(fhNum < -2400) {
    fhNum = 0;
  }
  $("fhc_ul").style.left = fhNum + "px";
  if(fhNum < -2400) {
    barNum = fhNum + 2400;
  }
  $("fhc_dBar").style.left = -(barNum / 2.75) + "px";
}
$("fhcShow").onmouseover = function() {
  $("fhc_d_box").style.display = "block";
  clearInterval(fhTimer);
}
$("fhc_d_box").onmouseover = function() {
  $("fhc_d_box").style.display = "block";
}
$("fhcShow").onmouseout = function() {
  $("fhc_d_box").style.display = "none";
  fhTimer = setInterval(marquee, 20);
}
//鼠标悬浮在标题也在暂停滚动
$("fhTit").onmouseover = function() {
  clearInterval(fhTimer);
}
$("fhTit").onmouseout = function() {
  fhTimer = setInterval(marquee, 20);
}
//滑块
$("fhc_dBar").onmousedown = function(event) {
  var event = event || window.event;
  var leftValue = event.clientX - this.offsetLeft;
  document.onmousemove = function(event) {
    var evt = event || window.event;
    var locationX = evt.clientX - leftValue;
    if(locationX < 0) {
      locationX = 0;
    }
    else if(locationX > 960 - 99) {
      locationX = 960 - 99;
    }
    $("fhc_dBar").style.left = locationX + "px";
    fhNum = -locationX  2.75;
    //如果选中了，就取消选中，防止出现bug
    window.getSelection ? window.getSelection().removeAllRanges() : document.selection.empty();
  }
  document.onmouseup = function() {
    document.onmousemove = null;//取消注册的这个事件
  }
}

<div class="fxhh_ctt">
  <div class="fh_c_show" id="fhcShow">
    <ul class="fh_c_under" id="fhc_ul">
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品1</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品2</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品3</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品4</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品5</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品6</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品7</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品8</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品9</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品10</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品11</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品12</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品1</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品2</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品3</p>
        <img src="" alt="">
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <img src="" alt="">
        <p class="botTit">商品4</p>
      </a></li>
      <li><a href=" " rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >
        <p class="Tit">商品5</p>
        <img src="" alt="">
      </a></li>
    </ul>
  </div>
  <!-- 滑块 -->
  <div class="fhc_box" id="fhc_d_box">
    <div class="fhc_drop" id="fhc_dBar"></div>
  </div>
  <!-- 滑块end -->
</div>
CSS代码
.fxhh .fxhh_ctt {
  width: 990px;
  background-color: #fff;
  float: left;
}
.fxhh .fxhh_ctt .fh_c_show .fh_c_under img {
  width: 150px;
  height: 150px;
}
.fxhh .fxhh_ctt .fh_c_show {
  width: 990px;
  height: 260px;
  background-color: #fff;
  overflow: hidden;
  position: relative;
}
.fxhh .fxhh_ctt .fh_c_show .fh_c_under {
  width: 2000%;
  position: absolute;
}
.fxhh .fxhh_ctt .fh_c_show .fh_c_under li {
  float: left;
  text-align: center;
  width: 150px;
  height: 180px;
  margin-: 40px;
  margin-right: 50px;
}
.fxhh .fxhh_ctt .fh_c_show .fh_c_under li .Tit {
  margin-bottom: 10px;
}
.fxhh .fxhh_ctt .fh_c_show .fh_c_under li .botTit {
  margin-: 10px;
}
.fxhh .fxhh_ctt .fhc_box {
  display: none;
  width: 960px;
  height: 4px;
  background-color: #f3f3f3;
  margin: 0 auto;
  position: absolute;
  : 250px;
  left: 210px;
}
.fxhh .fxhh_ctt .fhc_drop {
  width: 99px;
  height: 9px;
  border-radius: 4px;
  background-color: #d8d8d8;
  position: absolute;
  : -3px;
}