全国城市三级联动

html部分：

  <h1>全国城市三级联动</h1>
        <select id="s_province" name="s_province">
            <option value="省份">省份</option>
        </select>
        <select id="s_city" name="s_city">
            <option value="地级市">地级市</option>
        </select>
        <select id="s_county" name="s_county">
            <option value="市、县级市">市、县级市</option>
        </select>

 js部分：（此处需要引入area.js）

<script type="text/javascript">_init_area();</script>
<script type="text/javascript">
    var Gid  = document.getElementById ;
    var showArea = function(){
        Gid('show').innerHTML = "<h3>省" + Gid('s_province').value + " - 市" +
                Gid('s_city').value + " - 县/区" +
                Gid('s_county').value + "</h3>"
    };
    Gid('s_county').setAttribute('onchange','showArea()');
</script>