layui-admin js拼接 动态html

//只展示父级组织结构的权限
    form.on('select(role_select)', function(data){

        $.post("/admin/system/role/permission", {id: data.value}, function (result) {

            var html = '';
            html += '<label for="" class="layui-form-label">权限</label><div class="layui-input-block"><input type="checkbox" lay-filter="allIn" name="" lay-skin="primary" title="全选" value=""></div>';
            $.each(result.data,function(n,m){

                if (m.pid == 0){
                    html += '<div class="layui-input-block"><input type="checkbox" lay-filter="sonIn" class="permission" name="permissions[]" lay-skin="primary" title="'+m.describe+'" value="'+m.id+'"><div class="layui-input-block">';

                    $.each(result.data,function(i,j){

                        if (j.pid == m.id){
                            html += '<input id="'+ j.pid +'" type="checkbox" class="permission" name="permissions[]" lay-skin="primary" title="'+j.describe+'" value="'+j.id+'">';
                        }
                    });
                    html += '</div></div>';
                }
            });
            $('#permission').html(html);
            form.render();
        });
    });

遇到问题：最后需添加form.render()  来渲染数据。