<div class="ui-select">
     <span>使用加息券或现金券 <i class="icon-down lMar10"></i></span>
     <select name="" id="">
      <option value="10元现金券">10元现金券</option>
      <option value="20元现金券">20元现金券</option>
      <option value="30元现金券">30元现金券</option>
      <option value="40元现金券">40元现金券</option>
     </select>
    </div>

.ui-select{
 width:75%;
 height:63px;
 line-height:63px;
 background-color:#ECAFB4;
 color:#fff;
 padding:0 30px;
 text-align: left;
 position: relative;
}
select{
 width:100%;
 height:63px;
 line-height:33px;
 opacity: 0;
 position: absolute;
 top:0;
 left:0;
}

/*小三角图标*/
.icon-down{
 display: inline-block;
 width:30px;
 height:16px;
 background: url("../image/newWap/wapIcons.png") -168px -96px no-repeat;
}

$(".ui-select select").change(function(){
  $(this).prev("span").html($(this).find("option:selected").val()+'<i class="icon-down lMar10"></i>');
})
//select监测option的值的变化，添加到span中