easyui中的combogrid插件级联筛选

$("#selclass1").combogrid({
                    onChange: function (c1) {
                        $("#selclass2").combogrid({
                            disabled: false,
                            columns: [[
                                { field: 'id', title: '编号', width: "80px" },
                                { field: 'text', title: '名称', width: "120x" },
                                { field: 'miaoshu', title: '描述' }
                            ]],
                            loadFilter: function (data) {
                                var data1 = [];
                                for (var i in data) {
                                    //注意条件项的变化，-1 代表未匹配  
                                    if (c1.indexOf(data[i].parentid) > -1) {
                                        data1.push(data[i]);
                                    }
                                }
                                return data1;
                            }
                        });
                    }
                });

<div style="margin-bottom:10px">
                <select id="selclass1" name="c1_id" required="required" class="easyui-combogrid" style="width:100%" data-options="
                    panelWidth: 500,
                    idField: 'id',
                    textField: 'text',
                    url: 'ajax/class1list.json',
                    method: 'get',
                    rownumbers:true,
                    columns: [[
                        {field:'id',title:'编号',width:80},
                        {field:'text',title:'名称',width:120},
                        {field:'miaoshu',title:'描述'}
                    ]],
                    fitColumns: true,
                    label: '选择大分类:',
                    labelPosition: 'top'
                ">
            </select>
            </div>
            <div style="margin-bottom:10px">
                 <select id="selclass2" name="c2_id" class="easyui-combogrid" style="width:100%" data-options="
                    panelWidth: 500,
                    idField: 'id',
                    textField: 'text',
                    url: 'ajax/class2list.json',
                    method: 'get',
                    disabled: true,
                    rownumbers:true,
                    fitColumns: true,
                    label: '选择小分类:',
                    labelPosition: 'top'
                ">
            </select>
            </div>