   form = layui.form,
            tableSelect = layui.tableSelect;

        tableSelect.render({
            elem: '#demo',
            searchKey: 'my',
            checkedKey: 'id',
            searchPlaceholder: '自定义文字和name',
            table: {
                url: '../api/tableSelect.json',
                cols: [[
                    { type: 'checkbox' },
                    { field: 'id', title: 'ID', width: 100 },
                    { field: 'username', title: '姓名', width: 300 },
  