node.js - json数组中的 Node 分页

Question

我已经实现了以下分页代码，但无法使其工作。我需要使用以下 json 数据来完成它:

以下代码适用于Vt.js文件

const express = require('express');
const app = express();
const cors = require('cors');
var MongoClient = require('mongodb').MongoClient;
app.use(cors())
var url = "mongodb://localhost:27017/";

var pagination = require('pagination');
var paginator = pagination.create('search', {
  prelink: '/users',
  current: 2,
  rowsPerPage: 2,
  totalResult: 10020
});
console.log(paginator.render());

app.get('/users', function(req, res) {

  MongoClient.connect(url, function(err, db) {
    if (err)
      throw err;
    var dbo = db.db("MyNewDatabase");
    var data = dbo.collection("VirtualCapitalDB").find({}).toArray(function(err, result) {
      if (err)
        throw err;
      console.log(result);
      res.json(result);

      db.close();
    });
  });
})

app.listen(8080, ()=>console.log('Listening on port 8080'));

一旦你不分页访问它，你就可以获得以下 json 数组

[{
  "_id": "5bcb3c77dc56e939187c13a5",
  "firstname": "dumindu",
  "lastname": "nagasinghe",
  "videocount": 5
}, {
  "_id": "5bcb3ce6dc56e939187c13a9",
  "firstname": "cha",
  "lastname": "advv",
  "videocount": 10
}, {
  "_id": "5bcb3d4bdc56e939187c13ab",
  "firstname": "dvvs",
  "lastname": "scvssv",
  "videocount": 4
}, {
  "_id": "5bcb3d7adc56e939187c13ac",
  "firstname": "advav",
  "lastname": "dvdvv",
  "videocount": 5
}, {
  "_id": "5bcb40f7a768f83918480a2b",
  "firstname": "advav",
  "lastname": "dvdvv",
  "videocount": 5
}, {
  "_id": "5bcb4103a768f83918480a2c",
  "firstname": "advav",
  "lastname": "dvdvv",
  "videocount": 5
}, {
  "_id": "5bcb4106a768f83918480a2d",
  "firstname": "advav",
  "lastname": "dvdvv",
  "videocount": 5
}, {
  "_id": "5bcb4125a768f83918480a2e",
  "firstname": "advav",
  "lastname": "dvdvv",
  "videocount": 5
}]

但我需要添加分页并获取单页的 2 个数据对象。如何在代码中实现它？

Answer 1

编写数组项分页的最佳方法

paginator(items, page, per_page) {

  var page = page || 1,
  per_page = per_page || 10,
  offset = (page - 1) * per_page,

  paginatedItems = items.slice(offset).slice(0, per_page),
  total_pages = Math.ceil(items.length / per_page);
  return {
  page: page,
  per_page: per_page,
  pre_page: page - 1 ? page - 1 : null,
  next_page: (total_pages > page) ? page + 1 : null,
  total: items.length,
  total_pages: total_pages,
  data: paginatedItems
  };
}