vue 序號，翻頁時序號遞增

//使用
<el-table-column align="center" label="序號" type="index" :index="(index) => Nindex(index, queryParams.pageNum, queryParams.pageSize)"  />
//分頁序號發生變化
Vue.prototype.Nindex = function (index, pageNum, pageSize) {
    return index + 1 + (pageNum - 1) * pageSize;
};