我正在用Node.js和mongoose写一个web应用程序。如何对我从.find()调用得到的结果进行分页?我想要一个功能可比的“限制50,100”在SQL。


当前回答

以上回答是正确的。

只是一个插件,任何人谁是异步等待而不是 承诺! !

const findAllFoo = async (req, resp, next) => {
    const pageSize = 10;
    const currentPage = 1;

    try {
        const foos = await FooModel.find() // find all documents
            .skip(pageSize * (currentPage - 1)) // we will not retrieve all records, but will skip first 'n' records
            .limit(pageSize); // will limit/restrict the number of records to display

        const numberOfFoos = await FooModel.countDocuments(); // count the number of records for that model

        resp.setHeader('max-records', numberOfFoos);
        resp.status(200).json(foos);

    } catch (err) {
        resp.status(500).json({
            message: err
        });
    }
};

其他回答

let page,limit,skip,lastPage, query;
 page = req.params.page *1 || 1;  //This is the page,fetch from the server
 limit = req.params.limit * 1 || 1; //  This is the limit ,it also fetch from the server
 skip = (page - 1) * limit;   // Number of skip document
 lastPage = page * limit;   //last index 
 counts = await userModel.countDocuments() //Number of document in the collection

query = query.skip(skip).limit(limit) //current page

const paginate = {}

//For previous page
if(skip > 0) {
   paginate.prev = {
       page: page - 1,
       limit: limit
} 
//For next page
 if(lastPage < counts) {
  paginate.next = {
     page: page + 1,
     limit: limit
}
results = await query //Here is the final results of the query.

这是我在代码中做的

var paginate = 20;
var page = pageNumber;
MySchema.find({}).sort('mykey', 1).skip((pageNumber-1)*paginate).limit(paginate)
    .exec(function(err, result) {
        // Write some stuff here
    });

我就是这么做的。

最简单的分页插件。

https://www.npmjs.com/package/mongoose-paginate-v2

添加插件到一个模式,然后使用模型paginate方法:

var mongoose         = require('mongoose');
var mongoosePaginate = require('mongoose-paginate-v2');

var mySchema = new mongoose.Schema({ 
    /* your schema definition */ 
});

mySchema.plugin(mongoosePaginate);

var myModel = mongoose.model('SampleModel',  mySchema); 

myModel.paginate().then({}) // Usage
const ITEMS_PER_PAGE = 2;

exports.getProducts = (req, res, next) => {
  // + will turn the string to a number
  const page = +req.query.page || 1;
  let totalItems;
  //Product model
  Product.find()
    .countDocuments()
    .then((numProducts) => {
      totalItems = numProducts;
      return Product.find()
         //If query param is 3, since ITEMS_PER_PAGE = 2, we skip 2*2 items   
         // we show only 5th and 6th item
        .skip((page - 1) * ITEMS_PER_PAGE)
        .limit(ITEMS_PER_PAGE);
    })
    .then((products) => {
      res.render("shop/products", {
        // maybe sending the products object to templating engine
      });
    })
    .catch((err) => {
      const error = new Error(err);
      error.httpStatusCode = 500;
      // if you are set express error handler, use this
      // when we call next() with an argument passed in, we let express know, we skip all other middlewares, we move to error handling middleware

      return next(error);
    });
};

使用这个简单的插件。

https://github.com/WebGangster/mongoose-paginate-v2

安装

NPM安装mongoose- pagate -v2 使用 添加插件到一个模式,然后使用模型paginate方法:

Const mongoose = require('mongoose'); const mongoosePaginate = require(' mongoosePaginate -v2'); const mySchema =新的猫鼬。模式({ /*你的模式定义*/ }); mySchema.plugin (mongoosePaginate); const myModel =猫鼬。模型(SampleModel, mySchema); myModel.paginate().then({}) //使用方法