Node.js操作MongoDB数据库实例分析

npm init
npm i mongodb --save

{
 "name": "test",
 "version": "1.0.0",
 "description": "",
 "main": "app.js",
 "scripts": {
  "test": "echo \"Error: no test specified\" && exit 1"
 },
 "author": "",
 "license": "ISC",
 "dependencies": {
  "mongodb": "^3.1.1"
 }
}

// connect.js
const MongoClient = require('mongodb').MongoClient;
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'mydatabase';
// Use connect method to connect to the server
MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
 console.log("Connected suessfully to server");
 const db = client.db(dbName);
 client.close();
});

// insert.js
const MongoClient = require('mongodb').MongoClient;
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'mydatabase';
// 插入
var insertData = function (db, callback) {
 // 获取文档集合
 var collection = db.collection('collection3');
 var data = [{"name": "李二狗001", "age": 20}, {"name": "李二狗002", "age": 21}];
 // 插入文档
 collection.insert(data, function (err, result) {
  if(err) {
   console.log('Error: ' + err);
   return;
  }
  callback(result);
 })
}
// Use connect method to connect to the server
MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
 console.log("Connected suessfully to server");
 const db = client.db(dbName);
 insertData(db, function (result) {
  console.log(result);
  client.close();
 });
});

// find.js
const MongoClient = require('mongodb').MongoClient;
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'mydatabase';
// 查询
var findData = function (db, callback) {
 // 获取文档集合
 var collection = db.collection('collection3');
 var whereStr = {"name": "李二狗001"};
 // 查询文档
 collection.find(whereStr).toArray(function (err, result) {
  if(err) {
   console.log('Error: ' + err);
   return;
  }
  callback(result);
 })
}
// Use connect method to connect to the server
MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
 console.log("Connected suessfully to server");
 const db = client.db(dbName);
 findData(db, function (result) {
  console.log(result);
  client.close();
 })
});

// update.js
const MongoClient = require('mongodb').MongoClient;
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'mydatabase';
// 修改
var updateData = function (db, callback) {
 // 获取文档集合
 var collection = db.collection('collection3');
 var whereStr = {"name": "李二狗002"};
 var updateStr = {$set: {"age": 100}};
 // 修改文档
 collection.update(whereStr, updateStr, function (err, result) {
  if(err) {
   console.log('Error: ' + err);
   return;
  }
  callback(result);
 })
}
// Use connect method to connect to the server
MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
 console.log("Connected suessfully to server");
 const db = client.db(dbName);
 updateData(db, function (result) {
  console.log(result);
  client.close();
 })
});

// delete.js
const MongoClient = require('mongodb').MongoClient;
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'mydatabase';
// 删除
var delData = function (db, callback) {
 // 获取文档集合
 var collection = db.collection('collection3');
 var whereStr = {"name": "李二狗002"};
 // 删除文档
 collection.remove(whereStr, function (err, result) {
  if(err) {
   console.log('Error: ' + err);
   return;
  }
  callback(result);
 })
}
// Use connect method to connect to the server
MongoClient.connect(url, { useNewUrlParser: true }, function(err, client) {
 console.log("Connected suessfully to server");
 const db = client.db(dbName);
  delData(db, function (result) {
  console.log(result);
  client.close();
 })
});