尝试按照此处的示例过滤使用投影来排除_id._id仍然返回:
码
var MongoClient = require('mongodb').MongoClient;
var url = "mongodb://localhost:27017/db1";
MongoClient.connect(url, function (err, db) {
if (err) throw err;
var dbase = db.db("db1"); //here
dbase.collection("customers").find(
{},
{
_id: 0
}
).toArray(function(err, result) {
if (err) throw err;
console.log(result);
db.close();
});
});
Run Code Online (Sandbox Code Playgroud)
结果仍然如下返回:
[{_id:5a2bb2d6ee48575cb54c4365,姓名:'John',地址:'Highway 71'},{_ id:5a2bb2d6ee48575cb54c436d,姓名:'Susan',地址:'One way 98'},.... {_ id:5a2bb2d6ee48575cb54c4371,name :'Chuck',地址:'Main Road 989'},{_ id:5a2bb2d6ee48575cb54c4372,名称:'Viola',地址:'Sideway 1633'}]
理论上_id不应该是返回的一部分.这有什么不对?