下拉框默认字段 属性 + 清空下拉框 (脚本实现的 动态下拉框)

detext="城市"

<select class="input-medium m-wrap" tabindex="1" selectType="city" name="student.cityId" detext="城市" onchange="queryAreabyCity(this.value,'area')">  </select><select class="input-medium m-wra