首页 > 解决方案 > 使用 mongo nodejs require('file.js') module.exports 时如何处理结果

问题描述

我正在用 nodejs + express + mongodb + ejs 构建一个应用程序。

对于这个问题:我有 2 个文件(server.js + db.js)我把所有与 mongo 相关的东西都放在那个单独的文件(db.js)中,这样我就可以在那里进行所有数据库查询。问题:结果返回一个查询对象,我不知道如何在迭代中使用它(列出生成的文档),我将其发送给 ejs。当我执行 console.log(result.length) 时显示“未定义”。

有什么想法吗?

/* server.js: */

let db = require("./db.js");
app1.get("/page", function (req, res) {
    let result= db.getPLayers(); // console.log(result); ==> query object, see below => Q
    let qty = result.length; // console.log(qty); ==> undefined
    res.render('adm', { playersFound: result}); // sent to render result via ejs
}

/* db.js */

module.exports.getPLayers = function() {
    return Player.find({});
}

// => Q 这是我得到的查询对象:

> Query {   _mongooseOptions: {},   _transforms: [],   _hooks: Kareem {
> _pres: Map {}, _posts: Map {} },   _executionCount: 0,   mongooseCollection: 
NativeCollection {
>     collection: Collection { s: [Object] },
>     Promise: [Function: Promise],
>     _closed: false,
>     opts: { .... and lots more
>

标签: javascriptnode.jsmongodb

解决方案


// server.js
app1.get("/adm", function (req, res) {
let db = require("./db.js");
let playersList;
let teamsList;    
db.getPLayers().then(function () {        
    playersList = this.docs;
})
    .then(function () {
        db.getTeams().then(function () {                
            teamsList = this.docs;
        })
            .then(function () {                    
                res.render('adm', { playersFound: 
playersList, teamsFound: teamsList });//, teamsFound: dbteamsFound });
            });
    });
});
// db.js
exports.getPLayers = function(){
return Player.find({}, function (err, docs) {    
    this.docs=docs; console.log("==> db exporting getPlayers :"+ 
this.docs.length);  
});
}
exports.getTeams = function(){
return Team.find({}, function (err, docs) {    
     this.docs=docs; console.log("==> db exporting getTeams :"+ 
 this.docs.length);  
 });
 }

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