如何在nodejs中从mongodb获取问题对应的特定字段

npm install mongodb

const MongoClient = require('mongodb').MongoClient;

// MongoDB连接URL
const url = 'mongodb://localhost:27017';

// 数据库名称
const dbName = 'your-database-name';

// 字段名称
const fieldName = 'your-field-name';

MongoClient.connect(url, function(err, client) {
  if (err) {
    console.error('Failed to connect to MongoDB:', err);
    return;
  }

  console.log('Connected successfully to MongoDB');

  const db = client.db(dbName);
  const collection = db.collection('your-collection-name');

  // 查询特定字段
  collection.find({}, { projection: { _id: 0, [fieldName]: 1 } }).toArray(function(err, docs) {
    if (err) {
      console.error('Failed to find documents:', err);
      return;
    }

    console.log('Documents:', docs);
    client.close();
  });
});