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

这是一个示例函数,用于获得具有分页和限制选项的技能模型的结果

 export function get_skills(req, res){
     console.log('get_skills');
     var page = req.body.page; // 1 or 2
     var size = req.body.size; // 5 or 10 per page
     var query = {};
     if(page < 0 || page === 0)
     {
        result = {'status': 401,'message':'invalid page number,should start with 1'};
        return res.json(result);
     }
     query.skip = size * (page - 1)
     query.limit = size
     Skills.count({},function(err1,tot_count){ //to get the total count of skills
      if(err1)
      {
         res.json({
            status: 401,
            message:'something went wrong!',
            err: err,
         })
      }
      else 
      {
         Skills.find({},{},query).sort({'name':1}).exec(function(err,skill_doc){
             if(!err)
             {
                 res.json({
                     status: 200,
                     message:'Skills list',
                     data: data,
                     tot_count: tot_count,
                 })
             }
             else
             {
                 res.json({
                      status: 401,
                      message: 'something went wrong',
                      err: err
                 })
             }
        }) //Skills.find end
    }
 });//Skills.count end

}

其他回答

app.get("/:page",(req,res)=>{
        post.find({}).then((data)=>{
            let per_page = 5;
            let num_page = Number(req.params.page);
            let max_pages = Math.ceil(data.length/per_page);
            if(num_page == 0 || num_page > max_pages){
                res.render('404');
            }else{
                let starting = per_page*(num_page-1)
                let ending = per_page+starting
                res.render('posts', {posts:data.slice(starting,ending), pages: max_pages, current_page: num_page});
            }
        });
});
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.

使用ts-mongoose-pagination

    const trainers = await Trainer.paginate(
        { user: req.userId },
        {
            perPage: 3,
            page: 1,
            select: '-password, -createdAt -updatedAt -__v',
            sort: { createdAt: -1 },
        }
    )

    return res.status(200).json(trainers)
**//localhost:3000/asanas/?pageNo=1&size=3**

//requiring asanas model
const asanas = require("../models/asanas");


const fetchAllAsanasDao = () => {
    return new Promise((resolve, reject) => {

    var pageNo = parseInt(req.query.pageNo);
    var size = parseInt(req.query.size);
    var query = {};
        if (pageNo < 0 || pageNo === 0) {
            response = {
                "error": true,
                "message": "invalid page number, should start with 1"
            };
            return res.json(response);
        }
        query.skip = size * (pageNo - 1);
        query.limit = size;

  asanas
            .find(pageNo , size , query)
        .then((asanasResult) => {
                resolve(asanasResult);
            })
            .catch((error) => {
                reject(error);
            });

    });
}

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
        });
    }
};