data-options=“multiple:true”
<select id="txtstepNo" name="txtstepNo" class="easyui-combobox" style="width:130px;height:30px"
data-options="multiple:true">
<option value="10">造粒</option>
<option value="20">挤出</option>
<option value="30">辐照</option>
<option value="40">扩张</option>
<option value="50">包装</option>
</select>