TypeError: final argument to `executeOperation` must be a callback

1、错误描述

Administrator@USER-0GUONPPBHK MINGW64 /f/dojo/abcd/abcc/public/javascripts
$ node mongodb.js
F:\dojo\abcd\abcc\node_modules\mongodb\lib\utils.js:429
    throw new TypeError('final argument to `executeOperation` must be a callback');
    ^

TypeError: final argument to `executeOperation` must be a callback
    at executeOperation (F:\dojo\abcd\abcc\node_modules\mongodb\lib\utils.js:429:11)
    at MongoClient.connect (F:\dojo\abcd\abcc\node_modules\mongodb\lib\mongo_client.js:168:10)
    at Object.<anonymous> (F:\dojo\abcd\abcc\public\javascripts\mongodb.js:8:8)
    at Module._compile (internal/modules/cjs/loader.js:721:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:732:10)
    at Module.load (internal/modules/cjs/loader.js:620:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:560:12)
    at Function.Module._load (internal/modules/cjs/loader.js:552:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:774:12)
    at executeUserCode (internal/bootstrap/node.js:499:15)

2、错误原因

      添加了useNewUrlParser:true属性，需要一个回调函数

const MongoClient = require('mongodb').MongoClient;
const assert = require('assert');
const DB_URL = 'mongodb://localhost:27017/';
const DB_NAME = 'student';
const client = new MongoClient(DB_URL);

//查询数据
client.connect({useNewUrlParser:true},function(err){
    if(err) throw err;
    assert.equal(null,err);
    const db = client.db(DB_NAME);
    client.close();
});

3、解决办法

const MongoClient = require('mongodb').MongoClient;
const assert = require('assert');
const DB_URL = 'mongodb://localhost:27017/';
const DB_NAME = 'student';
const client = new MongoClient(DB_URL);

//查询数据
MongoClient.connect(DB_URL+DB_NAME,{useNewUrlParser:true},function(err,db){
    if(err) throw err;
    client.collection(DB_NAME),find({}).toArray(function(err,result){
        if(err) throw err;
        console.log(result);
        callback(result);
        db.close();
    });
});