layui多个复选框取值和赋值

HTML

                    <div class="layui-form-item" pane="">
                        <label class="layui-form-label">固定复选框</label>
                        <div class="layui-input-block" id="cbGuDing">
                            <input type="checkbox" name="cbtest" value="1" lay-skin="primary" title="写作"  /><%--checked=""--%>
                            <input type="checkbox" name="cbtest" value="2" lay-skin="primary" title="阅读" />
                            <input type="checkbox" name="cbtest" value="3" lay-skin="primary" title="游戏" />
                        </div>
                    </div>
<input type="hidden" id="hdfield09" value="<%=field09 %>" /><%--固定复选框--%>

JS,这里是赋值

$(function () {
            layui.use(['index', 'layer', 'form', 'laypage', 'laydate', 'upload', 'jquery', 'layedit'], function () {
                layer = layui.layer;
                form = layui.form;
                laypage = layui.laypage;
                laydate = layui.laydate;
                upload = layui.upload;
                layedit = layui.layedit;//注册layedit
                var $ = layui.jquery;
//固定复选框开始
                var arrCB = [];
                var strdata = $("#hdfield09").val();
                arrCB = strdata.split(",");
                for (var j = 0; j < arrCB.length; j++) {
                    var cbthis = $("input[name='cbtest']");
                    for (var i = 0; i < cbthis.length; i++) {
                        if (cbthis[i].value == arrCB[j]) {
                            cbthis[i].checked = true;
                        }
                    }
                }
                form.render("checkbox");//重新渲染页面checkbox控件
                //固定复选框结束
 });

取值

var arr_box = [];//固定复选框
            $('#cbGuDing input[type=checkbox]:checked').each(function () {
                arr_box.push($(this).val());
            });
alert(arr_box);