jquery treeview 数据库数据生成树

用juqery的treeview插件

现页面代码

     <select id="s1">
                                        <c:forEach items="${producttypeplist}" var="producttype">

                                            <option value="${producttype.id }">${producttype.name}</option>

                                         </c:forEach>   
                                         </select>

                                         <select id="s2">
                                        <option value="0">请选择</option>

                                         </select>   
js代码：
    <script type="text/javascript">
                         $("#s1").change(
                                function() {
                                    var s1val = $("#s1").val();
                                    $.post(baseUri + "/product/selectAllSonBypid", {
                                        pid : s1val
                                    }, function(data) {
                                        var str = "<option value=0>请选择</option>";
                                        $.each(data.producttypeplist, function(i, v) {
                                            str += "<option value='" + v.id + "'>" + v.name
                                                    + "</option>";
                                        });
                                        $("#s2").empty().append(str);
                                    }, "json");
                                });
                         $("#s2").change(
                                function() {
                                    $("#type").val($("#s2").val());
                                });
                    </script>

                大神们  救我