我对console.log显示来自NodeJS的nativeMongoDB驱动程序的ObjectId()对象的方式感到困惑。我使用console.log从MongoDB打印adslot文档:db.collection('adslots').findOne({_id:adslotId},(err,adslot)=>{console.log(adslot);}输出是adslot:{_id:57ef0b9b26d1d77b606bf271,name:'cspop',width:1,height:1,elemId:'dummy',active:true,updated:2016-10-01T0